Preheat the oven to 350°F and grease a casserole dish.
Cut the tops off the bell peppers then remove and discard the membrane and seeds.
Put them cut side up in the baking dish.
Heat the oil in a skillet, then add the sausage and beef.
Brown the meat and drain off the fat.
Stir in the onions, Montreal steak seasoning, red pepper flakes, and Worcestershire sauce.
Sauté for 5 minutes.
Turn the heat down to low.
Drain the tomatoes and add them along with the rice, stirring to mix.
Simmer for 5 minutes then mix in half the cheese.
Divide the meat mixture between the bell peppers.
Top with the rest of the cheese, cover with foil and bake for about 35 minutes or until the bell peppers are tender.
Broil the bell peppers for a couple of minutes to crisp up the cheese if you like.