Cook sausage in a large skillet until no longer pink, 4 to 6 minutes. Drain off excess fat. Add bell pepper and onion; cook until crisp. Add diced tomatoes and vegetable juice; cook and stir until boiling.
Remove from the heat and stir in rice. Cover the skillet and let stand until liquid is absorbed, 5 to 8 minutes.
Sprinkle mozzarella cheese over sausage, tomato, and rice mixture. Cover again and let stand until cheese is melted.
