Preheat your oven to 375°F (190°C).

Brown the ground beef in a large skillet over medium heat. Stir until it's no longer pink, then add the diced onion and bell peppers. Sauté for about 5 minutes until the vegetables are softened and fragrant.

Combine the canned tomatoes and frozen mixed vegetables into the skillet with the beef. Stir everything together and cook until it's heated through, about 3-4 minutes.

Layer half of the beef mixture in a greased baking dish, followed by half of the sliced potatoes. Repeat the layers, ensuring that the potatoes are on top this time.

Sprinkle the shredded cheese over the final layer of potatoes.

Cover the dish with foil and bake for 45 minutes. Remove the foil during the last 15 minutes.