Preheat your oven to 375°F (190°C).
Slice the tops off the bell peppers and remove the seeds.
In a skillet, heat olive oil over medium heat.
Sauté the diced onion and minced garlic until translucent.
Add the ground beef or turkey and cook until browned.
Stir in the cooked rice, diced tomatoes, Italian seasoning, salt, and pepper.
Fill each bell pepper with the meat and rice mixture.
Place the stuffed peppers in a baking dish.
Sprinkle shredded cheese on top of the peppers.
Cover with foil and bake for 20 minutes, then uncover and bake for an additional 10 minutes until cheese is bubbly.