01 - Preheat oven to 400°F. Line a baking sheet with parchment paper.
02 - In a large skillet over medium heat, cook ground beef, breaking it apart as it browns. Drain excess fat if necessary.
03 - Add chopped onion, bell pepper, and minced garlic to the skillet. Cook for 3 to 4 minutes until vegetables are soft.
04 - Stir in tomato sauce, tomato paste, ketchup, Worcestershire sauce, smoked paprika, brown sugar, salt, black pepper, and oregano. Simmer for 8 to 10 minutes until mixture is thickened, then remove from heat.
05 - Slice the baguette in half lengthwise. In a mixing bowl, combine softened butter, minced garlic, parsley, and 1/4 teaspoon salt.
06 - Spread garlic butter evenly over both bread halves. Arrange cut side up on the prepared baking sheet.
07 - Bake bread for 5 to 6 minutes until the surface is lightly golden. Remove from oven.
08 - Generously spoon sloppy joe filling onto the lower bread half. Sprinkle with mozzarella and Parmesan cheese.
09 - Return bread to oven for 5 to 6 minutes, until cheese is fully melted and bubbly.
10 - Place top half of bread over the filling, press gently, and slice into portions. Serve hot.