| Nonstick cooking spray or olive oil | roll into 16 balls (1.5 in), bake at 450°F 12–15 min until browned, then plate on paper towels | serve meatballs with sauce |
| 1 egg | beat egg and combine gently with beef, seasonings, panko, cheese, and cooled bacon-onion mixture |
| 1 pound ground beef (preferably 20-percent fat) |
| ½ teaspoon garlic powder |
| ½ teaspoon onion powder |
| 1 teaspoon kosher salt (such as Diamond Crystal) |
| Black pepper |
| ½ cup panko or standard bread crumbs |
| ½ cup shredded Cheddar |
| 4 slices thick-cut bacon, or 5 slices standard bacon | dice finely, cook in skillet with water until crisp, then cook diced onion in bacon fat until soft and cool |
| ¼ cup water |
| ½ medium yellow onion |
| ½ cup mayonnaise | make sauce by whisking together |
| 1 tablespoon ketchup |
| 1 tablespoon yellow mustard |
| 1 tablespoon sweet relish |
| 1 teaspoon Worcestershire sauce |