Air Fryer Sweet Potato Fries were a challenge for me. There, I've said it. What seems like the most simple air fryer recipe of all, wasn't. In theory, you should be able to peel your sweet potato, cut it and air fry it until the fries are nice and crispy. Every recipe I read made it sound that simple. So, why did that never work for me? Because I was missing one ingredient that took my soggy sweet potato fries to crispy without changing anything else.
I'm certainly not doubting the other recipes out there in internet land nor am I discounting the hundreds of people who post on social media about their air fryer sweet potato fries being perfectly crunchy. All I'm saying is, mine never turned out that way and I've been working on this recipe for at least a year. I focused on temperature, timing, and the size of the fries and had fail after fail after fail. Then I got to thinking about all the people who add a little cornstarch to their chicken wings to get them crispy and I thought, well I have nothing to lose here. Cornstarch on chicken wings has never made my chicken wings crisper, but at this point I was willing to try anything.
Would you like to save this recipe?
I will email this recipe page to you, so you can come back to it later!
Well, it worked! I finally had crispy sweet potato fries made in my Ninja Foodi air fryer! While I tested this recipe in my Ninja Foodi Pressure Cooker and Air Crisper using the Air Crisp function, you can make this recipe the same way in any air fryer, there just may be some time or temperature adjustments and I'll go over some things to consider in the Tips section below.
Tips for Making Homemade Sweet Potato Fries
- Don't crowd the fries. Try to get them in a single layer as much as possible and air fry in batches.
- Cut the sweet potato fries as uniformly as possible so they all cook at the same time. I recommend cutting them into ½" fries for the best outcome. Bigger fries, like steak fries or sweet potato wedges will take longer to cook and may require a lower temperature to avoid burning. The bigger the fry, the less crunchy it will be, in my experience.
- Know your air fryer and how it cooks. Air Fryers vary in wattage, size, and overall performance. Adjust time and temp accordingly. Oven air fryers tend to have more heat loss, so try increasing your temperature by 25-50℉ or 13-25℃ for the best results. This recipe was tested in the Ninja Foodi Pressure Cooker & Air Crisper and, in my experience, the times/ temps are about the same as a good quality basket style air fryer.
Ingredients & Substitutions
Sweet Potato
You want to pick out whole sweet potatoes that are uniform in shape, so when you cut them, the fries are also uniform which allows them to cook at the same time.
You can use white potatoes to make air fryer fries, but it is a different technique. See this video for how I make Air Fryer French Fries: Ninja Foodi Fresh Cut Fries Video
Seasonings
There are many different seasoning blends you can use to flavor your sweet potato fries or you can leave them plain. I find a little salt brings out the flavor in the fries, so, unless you can't have salt, I would definitely recommend using a little sea salt or kosher salt before air frying.
The seasoning blend I use is simple and very tasty. It's salt, onion powder, and garlic powder. If you are using garlic salt or onion salt, you can omit the sea salt.
A sweet option is cinnamon sugar made from 1 part cinnamon and 3 parts sugar. For just enough to sprinkle on the sweet potato fries, I would use ¼ teaspoon ground cinnamon and ¾ teaspoon sugar. One thing to keep in mind with sugar is it may caramelize as the fries cook and can burn. I recommend checking on the sweet potato fries and lowering the temperature of your air fryer if you see or smell any burnt sugar.
If you are looking for spicy sweet potato fries, try a spicy Cajun seasoning blend. Or, try mixing some cumin, chili powder, salt, and a little chipotle powder.
What you season your fries with is a matter of personal preference, of course, so get creative and mix up spices that you love and give it a try!
Cornstarch
Cornstarch, also known as cornflour, was the game changer for me. Adding just a little bit to the seasoned fries took them to the next level of crunchiness.
Now, I am certainly not pretending that these sweet potato fries are as crunchy as deep frying, they aren't. I'm not sure they ever could be, because hot oil is going to cook faster and crisp out the outside a lot more than hot air circulating around the fries. However, using the corn starch made a world of difference and I am quite happy with the crispness of these homemade sweet potato fries.
If you can't have or don't want to use cornstarch, then omit it. The only difference in the outcome will be a little less crispy.
Oil
I always get some pushback when I use oil in an air fryer recipe, which is almost 100% of the time. While air fryers are marketed as healthy and oil free alternatives to deep frying, a little bit of oil makes a huge difference when air frying foods that are breaded or that you want crispy like the fries. In this recipe, the oil helps the seasonings and cornstarch stick to the fries. In recipes like my chicken nuggets, the oil helps the breadcrumbs crisp up without drying out so the flavor and texture experiences is similar to deep frying. In most cases, you only need a small amount of oil, much less than what is absorbed when deep frying.
Can you omit it? Yes. Will your fries turn out as good? No.
The oil you use is completely up to you, but I've used olive oil and avocado oil with great success. If you want to use coconut oil, you will want to melt it first.
How to Cook Sweet Potato Fries in an Air Fryer
Making sweet potato fries is very easy and they turn out delicious in your air fryer. Except for an air fryer, you don't really need any special kitchen tools, but there are a few things that will be helpful.
Helpful Tools & Supplies for Recipe
- A sharp knife that is long enough to cut through your sweet potato
- A (affiliate link)cooling rack
- Large bowl or container for coating fries
Prep
Preheat the air fryer on the hottest setting for at least 10 minutes with the crisping plate or basket inside the appliance. On the Ninja Foodi, I use broil (grill) because it goes up to 450℉/230℃.
Peeling, cutting, and coating the sweet potato fries usually takes less than 10 minutes, but if you find it taking longer, then just keep the air fryer preheating until you are done.
Peel the sweet potato. I do this by cutting off the ends and then using a vegetable peeler to remove the skins. The skins are edible, so you can leave them on, but I'm not sure what the outcome would be because I've never tried it. Sweet potato skins aren't the same as Russet skins which I often leave on when making regular fries.
Once the sweet potato is peeled, give it a rinse under cold water and pat dry with a paper towel.
Since the sweet potato is cylindrical in shape, cutting it can be challenging because it can wobble on the cutting board. To avoid any knife accidents, I like to make a tiny slice off of the side of the sweet potato to create a flat surface so the sweet potato is stable on the cutting board.
Then, cut the sweet potato down the middle to create a larger flat surface on each half. Sit the sweet potato on the cutting board, flat side down and make slices about ½" thick. The number of slices you can make will depend on the size of your sweet potato.
Then cut each of those planks into ½" fries. The size of these fries are in between thick cut and shoestring fries. The picture makes them look a little bigger than they actually are. You may also notice that I only got 2 fries from the smaller planks. This will vary by the size and shape of your sweet potato, so don't go by number of slices as much as cutting them to be about ½" fries.
Once all the sweet potato fries are cut, place them into a large bowl or container. You want something large enough that you can toss them around without them spilling all over the place. You can use a large ziplock bag, if desired.
Add about 1 Tablespoon of oil (any neutral oil that you like) and sprinkle on about ½ of the seasoning you are using. Give them a good toss and add the remaining seasoning and toss again so the fries are lightly coated with oil and seasoning.
Next, sprinkle on the cornstarch and toss to coat. The cornstarch does not have to cover every bit of the sweet potato fries, but I do dry to toss them enough to get it spread out as evenly as possible.
Add a batch of the sweet potato fries to the preheated air fryer basket or crisping plate. The amount you can air fry at once will depend on your air fryer. In the Ninja Foodi Pressure Cooker & Air Crisper, I could fit half of the fries in at a time. Air fry or Air Crisp on 375℉/190℃ for 10 minutes. Wait at least 4-5 minutes before tossing to ensure the sweet potato fries have cooked enough not to fall apart.
I give them a toss about 5 minutes in and make sure they are back in a single layer. When the 10 minutes is up, remove the fries and place them on a cooling rack. The cooling rack is important because it prevents the fries from steaming ,which will cause them to get soggy.
As always, go by looks more than specified time. All air fryers aren't the same and you may find that you need more or less time.
Add the second batch and set the air fryer on 375℉/190℃ for 12 minutes. The reason for the increased time is so you can put the first batch back in so they are all hot and crispy when you serve them.
Toss the second batch after 5 minutes and cook 10 minutes or until you see them looking like the first batch. Add the first batch back into the air fryer, toss them together and continue cooking for another 2 minutes.
When done, dump all the fries onto a cooling rack and spread them out. Allow to cool for just a few minutes. This cooling period helps them crunch up even more!
Serve with your favorite dipping sauce or eat them plain! Enjoy!
Variations of Sweet Potato Fries
Cinnamon Sugar Sweet Potato Fries
If you like your sweet potato fries even sweeter, try tossing them in this seasoning blend. You may want to lower your temperature to 350℉/175℃ and cook each batch for 12 minutes to avoid burning the sugar.
After coating with oil, toss the sweet potato fries in this cinnamon sugar blend
- ½ teaspoon cinnamon
- 1½ teaspoons white sugar
- 1 (8-10) ounce Sweet Potato cut into fries
- 1 Tablespoon of oil
- 2 teaspoons cornstarch/cornflour
BBQ Sweet Potato Fries
Use your favorite BBQ rub to season the sweet potato fries or you can use the rub I use on my Ninja Foodi Ribs, it's absolutely delicious! Most BBQ rubs do contain sugar so I recommend decreasing the air fryer temperature to 350℉/175℃ and cook each batch for 12 minutes to avoid burning the sugar.
- 2 teaspoons of BBQ rub
Ranch Sweet Potato Fries
If you love all things ranch flavored, you will love it on the sweet potato fries. The cooking directions are the same as in the recipe, just toss in the dry ranch mix after coating in oil.
- 2 teaspoons dry ranch dressing mix
Jerk Seasoning Sweet Potato Fries
I recently made a recipe for Shrimp Rasta Pasta and the flavors in the jerk seasoning are amazing! I think it will be incredible on these sweet potato fries. You can either use a store-bought jerk seasoning mix or check out my jerk seasoning blend recipe: Jerk Seasoning Blend Recipe
Pumpkin Spice Sweet Potato Fries
Think of the flavors in a sweet potato pie, but on fries! Doesn't that sound good? You can add in sugar or omit it, but if you use the sugar decrease your air fryer temperature to 350℉/190℃ and increase your cooking time to about 12 minutes.
- 1 teaspoon white sugar
- ½ teaspoon cinnamon
- ¼ teaspoon nutmeg
- ¼ teaspoon allspice
These are just a few of the seasoning blends you can try. Get creative and blend up your favorite spices for a unique and delicious sweet potato fries that you will love!
Frequently Asked Questions
Do I have to soak sweet potato fries before air frying?
No, you don't have to soak them before air frying. The reason we soak white potatoes before making air fryer french fries is to remove the starch so they crisp up. Sweet potatoes don't have as much starch and, therefore, don't benefit from being soaked. In fact, I would advise against soaking them.
If you are following my recipe and your sweet potato fries aren't crispy after being cooled for a few minutes, then most likely there were too many in your air fryer basket. Overcrowding leads to steaming and they won't crisp up. It is important that you air fry them in a single layer or as close to a single layer as you can get. I found that one large sweet potato cooked in two batches in my air fryer worked great.
Sweet potato fries are best served right after air frying and after they have cooled for just a few minutes. This will give you the best crunchy sweet potato fries, however, if you have leftover fries and want to reheat them the next day here are some tips.
Allow the sweet potatoes to cool completely on a cooling rack. Place them in an airtight container and refrigerate. Bring the sweet potato fries out of the fridge and uncover them for about 30 minutes before reheating.
Preheat the air fryer on the hottest setting with the air fryer basket inside the appliance for a full 10 minutes. Put the sweet potato fries in the basket and set the temperature to air fry (or air crisp) at 325°F/160°C and air fry for 3-5 minutes or until they are warmed through and have crisped up a little bit.
Air Fryer Snacks and Side Dish Recipes
I love using the air crisp (air fry) function on my Ninja Foodi Pressure Cooker & Air Crisper to make fun, restaurant quality snacks and side dishes. Thes recipes can be made in any air fryer.
Air Fryer Sweet Potato Fries Recipe
Equipment
- Air Fryer
Ingredients
- 1 8-10 ounce Sweet Potato
- 1 Tablespoon olive oil
- 2 teaspoons cornstarch also called cornflour
Seasoning Blend
- 1 teaspoon fine grind sea salt or kosher salt
- ½ teaspoon garlic powder
- ½ teaspoon onion powder
Would you like to save this recipe?
I will email this recipe page to you, so you can come back to it later!
Instructions
- Preheat your air fryer on the hottest setting for 10 minutes. Make sure the air fryer basket or crisper plate is in the appliance during the preheat time. I use the Broil/Grill function on the NInja Foodi Pressure Cooker & Air Crisper because it reaches 450°F/230°C. If you are using a different air fryer, just use your hottest temperature setting.
- Peel your sweet potato to remove the skin. Rinse under cold water and pat dry with a paper towel.
- Mix up the spices in a small bowl.
- If your sweet potato is rolling on your cutting board, slice a tiny bit off of the side to make a flat surface. Cut the sweet potato in half. Place each flat side on your cutting board and make slices about ½" thick planks. Cut each plank into strips about ½" thick.
- Place the cut sweet potatoes into a large bowl and drizzle about 1 Tablespoon of olive oil or avocado oil over the top. Sprinkle on about ½ of the seasoning blend and toss the fries in the bowl. Add the remaining seasoning and toss again.
- Sprinkle the cornstarch over the top of the fries and toss to lightly coat the sweet potatoes with the cornstarch.
- Add as many sweet potato fries to the preheated air fryer as you can fit in one level. In the NInja Foodi PC & AC I can get half of them in at a time. Air Fry at 375°F/190°C for about 10 minutes. Toss them around at 5 minutes. Once they are golden brown and crispy, remove from the air fryer and place on a cooling rack.
- Repeat for the rest of the batches. When you get to the last batch, set the air fryer for 12 minutes and when the final batch has cooked 10 minutes add in previous batches and air fryer for 2 minutes, tossing them after 1 minute. This will get them all warmed back up again.
- Dump all the fries onto the cooling rack and spread them out. Let them cool a few minutes which adds to the crispiness. Serve & Enjoy!
France
Louise, I watched the video after I cooked my sweet potatoes. The written recipe said to use 2 teaspoons cornstarch/cornflour and you said to use 4 teaspoons on the video. I thought you’d like to know. These were delicious! Thank you!
~~France
Louise
Thanks for letting me know! I'm glad you enjoyed the fries!
Joseph Rotondo
My first try at this worked out well, except...the potatoes had dark almost burnt spots on them and tasted like they had a powder on them which would have been the corn starch. They had a mild crunch and good flavor but that powdery feeling was weird. Any ideas on that?
Thank You..
Louise
What air fryer did you use? It could be that the heat needs to be adjusted a bit or perhaps they were too close to the heating element which burned them in spots. Cutting them as evenly as possible may also help. Some dark areas are normal though and as long as they didn't taste burnt you really don't have to change anything. As far as the powdery feeling, the only thing I can think of is not enough oil to combine with the cornstarch. You shouldn't be able to see any of the cornstarch when they go into the air fryer as it all should have combined with the oil the fries are lightly coated with. If you see the cornstarch, try spritzing with a little more oil.
Ron
Another great airfryer score!
Louise
I'm glad you enjoyed them!
peita smith
I am allergic to all corn products, could I use arrowroot instead?
Louise
I haven't tried it with arrowroot, so I'm not sure. Maybe try just a few to see how it works. Some people say that they use baking powder and that works as well, but I haven't tried that either.
Corrie
I am sorry no picture was delicious
Louise
I'm so glad you enjoyed them!