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. Sauté until beef is browned throughout and drain any rendered fat.
03 - Stir in ketchup, yellow mustard, Worcestershire sauce, and chopped pickles. Remove skillet from heat and allow mixture to cool slightly.
04 - Flatten each biscuit round. Add 1 tablespoon of cooled beef mixture and 1/2 tablespoon shredded cheddar cheese to the center. Place one mozzarella cube on top.
05 - Fold the biscuit dough over the fillings, pinching edges tightly to enclose and form a ball. Place seam side down on the prepared baking sheet.
06 - Brush each dough ball with beaten egg and sprinkle with sesame seeds.
07 - Bake in preheated oven for 15–18 minutes, or until exterior is deeply golden and cooked through.
08 - Allow bombs to cool slightly before serving. Present with additional burger sauces such as ketchup or mustard for dipping.