A low carb, grain free, and delicious twist, perfect for any night of the week!
Slice the tops off of the peppers. Reserve the tops to dice and use in the meat mixture later. Clean out the seeds and ribs inside of the peppers and place them in a baking dish. Add about 1 cup of water to the bottom of the dish, and cover with foil. Place dish in the oven and preheat to 400º. This will give the peppers a head start to begin steaming while you make the filling.
While the oven is heating and the peppers are steaming, prepare the veggies. Chop the pepper "tops" into small cubes, dice the onions, and slice the mushrooms.
Remove the peppers from the oven and carefully uncover. Using a spoon, evenly fill the peppers with the meat mixture to the brim. Fill until the mixture is used up.
Re-cover the peppers with foil, and place back into the oven for 20 minutes. Remove from oven and take off foil. Add cheese slices (I didn't need a full slice for each one). Place back into the oven and cook uncovered for another 8 minutes.