01 - Set 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, until browned. Drain excess fat if necessary.
03 - Stir in chopped onion, green bell pepper, and minced garlic. Cook for 3 to 4 minutes until vegetables are softened.
04 - Add tomato sauce, tomato paste, ketchup, Worcestershire sauce, smoked paprika, brown sugar, salt, black pepper, and oregano. Simmer 8 to 10 minutes until thickened. Remove from heat.
05 - Slice baguette in half lengthwise. In a mixing bowl, mix softened butter, minced garlic, chopped parsley, and 1/4 teaspoon salt until combined.
06 - Evenly spread garlic butter over cut side of both bread halves. Place bread, cut side up, on prepared baking sheet and bake for 5 to 6 minutes until lightly golden. Remove from oven.
07 - Spoon hot sloppy joe mixture onto one cut side of each bread piece. Top with mozzarella and Parmesan cheese.
08 - Return bread to oven and bake 5 to 6 minutes, or until cheese is melted and bubbly.
09 - Sandwich the top and bottom bread halves together, press gently, and cut into individual servings. Serve immediately while hot.