01 - Preheat oven to 400 degrees Fahrenheit. Line a baking sheet with parchment paper.
02 - In a large skillet over medium heat, cook the ground beef, breaking it apart with a wooden spoon, until fully browned. Drain excess fat if necessary.
03 - Add chopped onion, bell pepper, and minced garlic to the skillet with the beef. Cook for 3 to 4 minutes, stirring, until the vegetables are tender.
04 - Stir in tomato sauce, tomato paste, ketchup, Worcestershire sauce, smoked paprika, brown sugar, salt, black pepper, and dried oregano. Simmer over medium-low heat for 8 to 10 minutes until the mixture thickens. Remove from heat.
05 - Slice the baguette in half lengthwise. In a mixing bowl, combine softened butter, minced garlic, chopped parsley, and salt until evenly blended.
06 - Evenly spread the garlic butter over the cut sides of both bread halves. Place cut-side up on the prepared baking sheet.
07 - Bake in the oven for 5 to 6 minutes, or until the bread is lightly golden around the edges. Remove from the oven.
08 - Spoon the hot sloppy joe filling generously onto one half of each bread loaf. Top evenly with mozzarella and Parmesan cheese.
09 - Return the assembled bread to the oven and bake for 5 to 6 minutes, or until the cheese is melted and bubbly.
10 - Place the remaining bread halves on top to create sandwiches, pressing gently. Slice into portions and serve immediately while hot.