01 - Preheat oven to 400°F. Line a baking sheet with parchment paper.
02 - In a skillet over medium heat, cook the diced onion until translucent, about 3 minutes. Add ground beef, garlic powder, salt, and black pepper. Cook until the beef is browned and crumbly, then drain off excess fat.
03 - Stir in ketchup, mustard, Worcestershire sauce, and pickles. Mix thoroughly, then remove skillet from heat. Allow mixture to cool slightly.
04 - Flatten each biscuit round. Add 1 tablespoon cooked beef mixture and 1/2 tablespoon shredded cheddar to the center. Top each with a mozzarella cube.
05 - Fold biscuit dough around the filling, pinching edges to seal tightly and form a ball. Place seam side down onto the prepared baking sheet.
06 - Brush each assembled bomb with beaten egg and sprinkle the tops with sesame seeds.
07 - Bake in the oven for 15 to 18 minutes, or until the bombs are golden brown and cooked through.
08 - Allow to cool slightly before serving. Pair with ketchup, mustard, or your preferred burger sauce for dipping.