Turn your instant pot onto sauté mode. Once hot, pour in your vegetable oil. Add the chicken breasts to your pot. You don’t want to leave them in too long, you are just lightly sautéing them until they cook on the outside. Once slightly cooked on each side, remove and set aside.
Add the tomato sauce, garlic, and 1 tbsp fresh basil to your instant pot.
Add the chicken breasts back to the pot and cover them in the sauce.
Cook in your instant pot on high for 10 minutes. Once that time is done, manually release pressure by releasing the valve.
On top of each chicken breast, place the mozzarella cheese, followed by the Parmesan cheese, and the remaining basil. Put the lid back on your instant pot continuing to keep it on warm setting and allow the cheese to melt for about 5 to 7 minutes.
Transfer to a plate and enjoy!