Set your oven to 375°F (190°C). Lightly grease a muffin tin or use silicone cupcake liners to prevent sticking.
In a large bowl, combine ground beef, breadcrumbs, egg, ketchup, milk, garlic powder, onion powder, salt, and pepper. Mix gently with clean hands or a spoon until just combined—don’t overmix.
Spoon the meat mixture into each muffin cup, pressing it down and filling to the top. Bake for 20–25 minutes, until fully cooked and nicely browned on top.
While the meatloafs bake, whip mashed potatoes until smooth and fluffy. Add a splash of milk or melted butter if needed for a silky texture that’s easy to pipe.
Let the cupcakes rest in the tin for 5 minutes, then carefully remove. Pipe the whipped potatoes on top using a star piping tip for a classic cupcake look. Sprinkle chopped chives over the potato topping and serve warm.