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 browned, breaking it apart with a spoon. Drain excess fat if needed.
03 - Add chopped onion, bell pepper, and minced garlic to the 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 oregano. Simmer 8 to 10 minutes until mixture thickens. Remove from heat.
05 - Slice the baguette in half lengthwise. In a mixing bowl, combine softened butter, finely minced garlic, parsley, and salt.
06 - Evenly spread garlic butter over bread halves. Arrange, cut side up, on the prepared baking sheet.
07 - Bake in preheated oven for 5 to 6 minutes until the edges are lightly golden. Remove from oven.
08 - Generously spoon sloppy joe filling onto one half of each bread piece. Sprinkle evenly with mozzarella and Parmesan cheese.
09 - Return bread to oven and bake 5 to 6 minutes, until cheese is melted and bubbly.
10 - Place the remaining bread halves on top, press gently to sandwich, and slice for serving. Serve immediately while hot.