01 - Preheat oven to 400°F. Line a baking sheet with parchment paper.
02 - In a large skillet over medium heat, cook ground beef until evenly browned, breaking it into crumbles. Drain excess fat as needed.
03 - Add chopped onion, green bell pepper, and minced garlic to skillet. Sauté for 3 to 4 minutes until vegetables are softened.
04 - Incorporate tomato sauce, tomato paste, ketchup, Worcestershire sauce, smoked paprika, brown sugar, salt, black pepper, and dried oregano. Simmer on medium-low heat for 8 to 10 minutes until mixture thickens. Remove from heat.
05 - Slice baguette in half lengthwise. In a mixing bowl, blend softened butter, minced garlic, chopped parsley, and salt until well combined.
06 - Spread garlic butter evenly over cut sides of both baguette halves. Arrange bread, cut side up, on prepared baking sheet.
07 - Bake for 5 to 6 minutes until bread turns lightly golden. Remove bread from oven.
08 - Spoon warm sloppy joe filling generously onto one half of each bread piece. Evenly sprinkle mozzarella and Parmesan cheeses over the filling.
09 - Return assembled bread to oven and bake for an additional 5 to 6 minutes until cheese is fully melted and bubbly.
10 - Press top halves of bread onto bottoms to form sandwiches. Slice into individual servings and serve hot.