Skillet or Dutch oven instructions are very similar, see the recipe notes for the changes.
Prep for the Recipe
If you are using roasted garlic and homemade croutons make those now.
Cut the onions in half from stem to root and remove the outer skin. Cut the stem end off and leave the root end intact to hold the onion together. Lay half of the onion on a cutting board with the flat surface facing down. Using a sharp knife, cut ½" slices. Repeat for all of the onions.
3 pounds sweet onions
Gather the remaining ingredients and measure out the spices. 1 teaspoon of the salt will be used to season the onions and the remaining ½ teaspoon is for seasoning the beef slices.
1½ teaspoons fine grind sea salt, 1 teaspoon black pepper, 1 teaspoon dried thyme leaves
Carmelizing the Onions
Turn sear/sauté function on high. Add the Ghee, olive oil, or clarified butter to the inner pot of the Ninja Foodi or Instant Pot pressure cooker. If you are using a stainless steel inner pot, turn the sauté function down to medium high.
4 Tablespoons Ghee or clarified butter
Add in the sliced onions, 1 teaspoon of salt, 1 teaspoon black pepper, and 1 teaspoon of dried thyme leaves. Using tongs, stir and toss around the onions to distribute the seasonings and coat them with the ghee/oil.
Caramelizing the onions will take 25-30 minutes and it's important for the development of flavor in the dish. Leave the onions alone for about 10 minutes so they start to brown. Adjust your heat as necessary and don't let the onions burn.
After about 10 minutes, toss the onions around again to move the lesser cooked onions to the bottom of the pot so they brown evenly. Continue to sauté and toss every 5 minutes until the onions are a deep golden brown and have reduced to about 2-2½ cups. Remove half of the onions if you want more texture in the final dish and set them aside.
Cooking the beef
While the onions are sautéing, salt the thinly sliced beef with ½ teaspoon of salt.
Add the beef to the onions and continue sautéing with the onions. Add in the cloves of roasted garlic, use the whole bulb. Cook the beef until it is no longer pink. This only takes a few minutes.
1 pound thinly sliced beef, 1 bulb roasted garlic
Deglaze & Pressure Cook
While the pot is still on high sear/sauté pour in the sherry and scrape the bottom of pot to remove anything that may be stuck on the bottom. If you don't want to use sherry, you can use beef broth or even water.
½ cup cooking sherry
Add in the beef consommé and French onion soup. If you aren't using those ingredients, use 32 ounces of beef broth.
Stir in the Rigatoni pasta and try to get as much of the pasta under the liquid as possible. Put the pressure lid on and turn the valve to seal. Set the pressure cooker to high pressure and the time to 4 minutes. It will take about 8 minutes to come to pressure.
16 ounces Rigatoni pasta
For al dente pasta, do an immediate release after the 4 minutes of pressure cook time. For softer pasta, allow the pot to natural release for 2 minutes and then manually release the remaining pressure.
Open the lid and stir everything together. You may notice the pasta on the top isn't quite as done, don't worry, it finishes cooking as it sits in the pot.
Add back in the onions you took out before pressure cooking and stir. Take out a spoonful and taste it for seasonings. You may need more salt, pepper, or thyme depending on what liquid you used.
Add the Toppings & Bake
If you are using the Ninja Foodi or an Instant Pot with a crisping lid, you can do everything right in the main pot or you can transfer the pasta to a 9 x 13 deep casserole dish and finish in the oven if you want to serve it as a casserole. See the recipe notes for details
Cover the past with a layer of croutons and then cover the croutons with the shredded cheese. If using slices of provolone, lay them in a single layer to cover the shredded cheese. Try to make sure all the pasta is covered and not poking out or it will start to get crunchy when baked.
Close the crisping lid and select bake/roast and set the temperature to 375℉/190℃ and bake for 5-10 minutes or until the cheese has melted and is golden brown.
Skillet or Dutch Oven DirectionsUse a 6 quart Dutch oven or Skillet that is oven safe. If using something smaller, cut the recipe in half. Cut the onions into ½" strips. Add 4 Tablespoons of oil, butter, or ghee into the pan and turn the heat on medium-high. Add the sliced onions and seasonings and toss with tongs to coat in the butter or oil.Cook over medium-high heat for about 7 minutes and then toss the onions around. They should be starting to brown. If they aren't browning, turn your heat up and if they are browning too quickly, turn the heat down.Continue to sauté the onions for 20-30 minutes or until they turn a deep golden brown and are reduced to about 2 cups of onions.Remove half of the onions if you want to keep more texture in the final dish. Season the thinly sliced beef with salt and add to the onions along with the roasted garlic cloves. Stir and sauté until the beef is no longer pink. This will take about 5 minutes or so.Deglaze the pan with 1 cup of sherry or beef broth. Add the beef consomme and soup for a total of 31.5 ounces of liquid.Bring the liquid to a boil and add the Rigatoni pasta.Reduce the heat to medium and cover the skillet with a lid. Simmer for about 10-12 minutes or until the pasta is al dente. Taste for seasonings and add salt and pepper to taste.Add the croutons and grated cheese on top and place the skillet or dutch oven in a preheated oven on 400℉/200℃ and bake for 10-12 minutes or until the cheese has melted and is bubbly and brown.Serve & Enjoy!