1/2 pound ground beef 
1 cup cooked rice
Salt, to taste 
Black pepper, to taste 
1 (15-ounce) can tomato sauce
1/3 cup chopped sweet onion
1/8 teaspoon garlic powder
1 cup shredded mozzarella cheese
4 large bell peppers (with tops, seeds and membranes removed)
Shredded cheddar cheese

Heat oven to 350. In a large skillet, brown ground beef. Drain excess fat. Add next seven ingredients. Simmer 5 minutes, then spoon mixture into peppers. Bake in an 8-inch-by-8-inch dish for 30 to 40 minutes. In the last few minutes of baking, remove dish, top peppers with shredded cheddar and place in oven until melted.

Recipe Note: Make this low-carb by using spaghetti squash instead of rice.