Prepare by cutting the peppers top off and scooping out the seeds and membrane. You'll need to blanch peppers in boiling water over medium high heat for about 6 minutes so peppers are tender and get rid of bitter flavor.
Cook your rice in Instant Pot or rice cooker while you’re doing that brown your lean ground beef, turkey, sausage or chicken until it is no longer pink.
When rice and ground beef are cooked, mix them together with your tomato sauce (spaghetti sauce or diced tomatoes), salt, and 1/2 cup of your cheddar or Monterey jack cheese.
Put blanced peppers in a muffin tin or baking dish so they don’t fall over and fill them with your rice mixture. Cook the peppers in the oven at 350 degrees for maybe 15 - 20 minutes just to meld all the flavors together.
If you want to top with cheese do so the last 5 minutes or so just cheese is melted and lightly browned.