Cook your ground beef. Set the Instant Pot to saute and spray with nonstick spray. Break up into small chunks with a spatula or wooden spoon until no pink is left.
Cut the tops off of the peppers. Use a cutting board and sharp knife to cut the stems off of your bell peppers and remove any seeds.
Add riced cauliflower to the bottom 1/2 of your peppers. Place the trivet inside of your Instant Pot. Put peppers on top of the trivet and stuff them half full with tomato sauce and riced cauliflower.
Top with seasoned ground beef. Fill the remaining half of the peppers with your seasoned ground beef.
Add Cheese. Sprinkle the stuffed peppers with shredded cheese.
Cook under high pressure. Add 1/2 cup of water to the bottom of the Instant Pot liner, careful not to pour the water onto the stuffed peppers. Cook for 12 minutes under high pressure.
Quick release. Quickly release all pressure from the pot.
Remove from the Instant Pot and enjoy. Carefully remove the peppers from the top of the trivet and plate.