Place the potatoes directly in the bottom of your air fryer insert. This can be the inner pot in the Ninja Foodi or the drawer of other air fryers. Add the water and air fry at 400℉/200℃ until the potatoes are fork-tender. The time this takes will depend on your air fryer and the size of the potatoes, but 15 minutes is about average.
1.5 pounds small potatoes, ¼ cup water
Once the potatoes are fork tender, you can either smash them directly in the air fryer or move them to a flat tray or cutting board to smash them with something heavy like the flat side of a meat tenderizer or mallet. The bottom of a glass will also work. I like to cover the potatoes with parchment to keep the potatoes in place and not have them splatter when they are smashed.
Return the smashed potatoes to the air fryer if you removed them and season with salt and pepper or whatever other seasonings you like. Top with pieces of butter and air fry at 400℉/200℃ until they become golden brown and as crispy as you like. See the recipe notes for various suggested timings.
½ teaspoon fine grind sea salt, ¼ teaspoon black pepper, 3 Tablespoons butter
Add the parsley and toss to coat the potatoes. This is entirely optional but does add a pop of color. Serve and enjoy!