Step 1: Preheat your oven to 375°F (190°C). Line a large baking sheet with parchment paper.
Step 2: In a large skillet, heat olive oil over medium heat. Add ground beef and finely diced onion (if using). Cook, breaking up the meat with a spoon, until browned. Drain any excess grease.
Step 3: Stir in garlic powder, onion powder, salt, and pepper. Cook for another minute until fragrant. Remove from heat.
Step 4: In a medium bowl, combine the cooked ground beef mixture, crumbled bacon, ketchup/pizza sauce, and yellow mustard (if using). Mix well.
Step 5: Unroll each can of crescent roll dough onto a clean surface. Pinch together the perforations to form two rectangular sheets. Cut each sheet into 4 squares, resulting in 8 squares total.
Step 6: On one half of each dough square, place a spoonful of the beef and bacon mixture, leaving a small border. Top with a generous sprinkle of both cheddar and mozzarella cheese.
Step 7: Fold the other half of the dough over the filling to create a pocket. Press the edges firmly with your fingers or a fork to seal completely.
Step 8: Transfer the sealed pockets to the prepared baking sheet.
Step 9: Bake for 12-15 minutes, or until the pockets are golden brown and puffed up.
Step 10: Let cool for a few minutes before serving. Be careful, the filling will be hot and ooey-gooey!