Preheat the oven to 375°F (190°C).

Cut the tops off the bell peppers and remove the seeds.

In a skillet, cook the ground beef over medium heat until browned. Drain excess fat.

Add chopped onion and minced garlic to the skillet and cook until softened.

Stir in the cooked rice, diced tomatoes, Italian seasoning, salt, and pepper. Mix well.

Stuff each bell pepper with the beef and rice mixture, and place them upright in a baking dish.

Top each stuffed pepper with shredded cheese.

Cover the baking dish with foil and bake for 25 minutes. Remove foil and bake for an additional 5 minutes until cheese is bubbly.