01 - Preheat the oven to 400°F. Line a baking sheet with parchment paper.
02 - In a large skillet over medium heat, cook the ground beef until browned, breaking it apart as it cooks. Drain excess fat if necessary.
03 - Add chopped onion, green bell pepper, and minced garlic to the skillet. Cook for 3 to 4 minutes until the vegetables are softened.
04 - Stir in tomato sauce, tomato paste, ketchup, Worcestershire sauce, smoked paprika, brown sugar, salt, black pepper, and oregano. Allow the mixture to simmer for 8 to 10 minutes until thickened, then remove from heat.
05 - Slice the baguette in half lengthwise. In a small bowl, blend softened butter with minced garlic, chopped parsley, and salt.
06 - Spread garlic butter evenly over both bread halves and place cut side up on the prepared baking sheet. Bake for 5 to 6 minutes until lightly golden.
07 - Generously spoon sloppy joe filling onto one half of each toasted bread piece. Sprinkle evenly with shredded mozzarella and grated Parmesan cheese.
08 - Return the bread to the oven for another 5 to 6 minutes, until cheese is melted and bubbly.
09 - Place the remaining bread halves on top, press gently to sandwich, and use a sharp knife to cut into portions. Serve hot.