In a large skillet, brown the ground beef over medium-high heat. Drain off any excess grease.
1 pound ground beef
Add the chopped onion and bell pepper (if using) to the skillet. Cook until softened, about 5 minutes.
1 medium onion, 1 green bell pepper
Stir in the tomato sauce, ketchup, Worcestershire sauce, brown sugar, mustard, garlic powder, salt, and pepper. Bring to a simmer, then reduce heat and cook for 10-15 minutes, stirring occasionally, until the sauce has thickened slightly.
15 ounce tomato sauce, 1/4 cup ketchup, 2 tablespoons Worcestershire sauce, 1 tablespoon brown sugar, 1 teaspoon yellow mustard, 1/2 teaspoon garlic powder, Salt and pepper
Preheat oven to 375°F (190°C). Place the halved French bread on a baking sheet.
1 loaf French bread
Spread the sloppy joe mixture evenly over the French bread halves.
Sprinkle the cheddar and mozzarella cheese over the sloppy joe mixture.
1 cup shredded cheddar cheese, 1/2 cup shredded mozzarella cheese
Bake for 10-12 minutes, or until the cheese is melted and bubbly and the bread is golden brown.
Remove from the oven and add any desired toppings, such as sliced olives, diced tomatoes, or chopped green onions.
sliced olives, diced tomatoes, chopped green onions
Slice and serve warm directly from the oven. Enjoy!