How to Make It
Set instant pot to “saute”, and add oil. Add onion to hot oil, and cook, stirring constantly, 3 minutes. Add mushrooms, eggplant, garlic, salt, and pepper, and cook, stirring often, 3 minutes. Stir in water, and press “cancel” on instant pot.
Pour in pasta (do not stir). Pour marinara evenly over noodles (do not stir). Place lid on top of instant pot, and set to high pressure for 4 minutes.
Manually release pressure at the end of cooking process. Stir in fresh parsley and basil; serve hot.
If using “cheese”, stir 1 cup into the pasta mixture, and sprinkle remaining cheese on top. Let stand 5 minutes until cheese melts.