Bring a pot of lightly salted water to a boil; cook green bell pepper until tender, about 5 minutes. Remove with a slotted spoon and cool. Chop into small pieces.
Bring rice and water to a boil in a saucepan. Reduce heat to medium-low, cover, and simmer until the rice is tender, and the liquid has been absorbed, 20 to 25 minutes.
Cook and stir beef and onion in a skillet over medium heat until beef is browned and crumbly, and onion is softened, 10 to 15 minutes. Add chopped green bell pepper, cooked rice, tomatoes, Worcestershire sauce, and tomato soup; stir to combine. Cover and simmer until heated through, about 15 minutes.
Spoon beef and rice mixture into individual bowls; top each serving with Cheddar cheese.