Step 1: Heat olive oil in a large skillet over medium heat. Add the ground beef and finely chopped onion. Cook, breaking up the beef with a spoon, until no pink remains and the onion is softened.
Step 2: Drain any excess grease from the skillet. Return the beef to the heat and stir in the salt, black pepper, garlic powder, and onion powder. Cook for another 1-2 minutes, allowing the flavors to meld. Remove from heat and set aside to cool slightly.
Step 3: Preheat your oven to 375°F (190°C). Line a large baking sheet with parchment paper.
Step 4: Unroll the refrigerated crescent roll dough and separate it into individual triangles. If your crescent rolls come in sheets, pinch the seams together and then cut into 8 squares or triangles.
Step 5: Place a spoonful of the seasoned ground beef mixture onto the wide end of each crescent roll triangle. Top the beef with a quarter slice of American cheese.
Step 6: Fold the dough over the filling, pulling the wide end up and over, then rolling towards the narrow tip. Pinch all edges firmly to completely seal the filling inside, ensuring no cheese leaks out during baking. Shape them into a 'bomb' or ball as much as possible.
Step 7: In a small bowl, combine the melted unsalted butter, minced fresh garlic, and grated Parmesan cheese.
Step 8: Arrange the assembled cheeseburger bombs on the prepared baking sheet. Generously brush the garlic Parmesan butter mixture over the top of each bomb.
Step 9: Bake for 12-15 minutes, or until the crescent rolls are golden brown and puffed. The exact time may vary based on your oven and the size of your bombs.
Step 10: Carefully remove the bombs from the oven. Garnish with fresh chopped parsley, if desired, and serve warm.