Press Sauté to turn Instant Pot on and begin heating it up.
If meat is lean, drizzle olive oil in bottom of heating pot. Brown Italian sausage (or other ground meat, if using) in pot.
To make the spaghetti sauce, add basil, oregano, and fennel to browning meat.
Stir in onions and bell peppers, and saute for 2-3 minutes. Add garlic and stir in for 1 minute.
Pour in pasta and crushed tomatoes.
Using empty can of crushed tomatoes to measure, add 28 ounces of fresh water or chicken broth and pour into pot over the sauce and meat.
Stir this all together, and try to push as much pasta down into the sauce as possible.
Place lid on Instant Pot and lock it in place.
Check to make sure valve is on Sealing.
Press to turn machine off from sautéing meat.
Press Manual or Pressure Cook and then <+> or <-> to adjust time to HALF of lowest minutes of cooking time indicated on the box of pasta.
Wait 10 seconds. Pot will beep to let you know it is starting to heat up. It should take approximately 12-15 minutes to come to pressure. The number of minutes that were entered will appear on the screen and begin to count down to zero.
Carefully, keeping face and hands away from the steam release valve, move it to Venting. This is a Quick Release. Should food begin to spray out, simply close the valve and wait a couple of minutes.
After it is cooked, stir well and taste test. Be careful! It is extremely hot immediately after you release the pot. If you find it tastes too tart, sprinkle in 1-2 teaspoons of sugar to cut the acidity of the tomatoes.
You can use jarred spaghetti sauce, and pour sauce in and add slightly less than 1 1/2 jars of water. This recipe is based on a total of about 56 ounces of liquid, and sauce jars vary in size. Note that jarred spaghetti sauce often contains sugar already.Variations
Cajun Jambalaya Pasta: Use sliced smoked or andouille sausage instead of Italian Sausage. Add diced onions, bell pepper, and celery, garlic, thyme, and bay leaf. Crushed or diced tomatoes instead of sauce. Use chicken broth instead of water. Add red pepper flakes or hot sauce to taste.
Florentine Pasta: Add frozen chopped spinach and add cooked, drained beans (garbanzo, kidney, or cannellini).
Low-carb/Whole food version: Use cooked Spaghetti Squash as the pasta. Put in pot and stir as directed above. Set on Manual, high pressure for 2 minutes, and Quick Release.