To the bowl of your Instant pot, combine one chicken breast, sliced peppers and onions, and 1 cup of your favorite salsa. Press the "poultry" button to cook your chicken on high pressure for 12 minutes. Let it depressurize naturally if you have time. Otherwise, carefully release it without burning yourself on the steam.
Shred the chicken with two forks. You could also cut it up with a knife, if that's your preference.
Preheat the oven to 400ºF.
Spread ½ cup of salsa on the bottom of your casserole dish.
Set out 4 tortillas. Add ½ cup of chicken and veggie mix to each tortilla (save any leftovers for meal prep). Add a little sprinkle of cheese if you want.
Roll each enchilada up, and place it into the casserole dish seam-side-down.
Top the enchiladas with the remaining ½ cup of salsa. Sprinkle cheddar on top.
Bake for 25 to 30 minutes until the cheese is browned to your liking.
For my photos, I topped mine with diced tomato, sliced black olives, sliced avocado, and light sour cream. These are entirely optional, but delicious.