Preheat your oven to 350°F (175°C) and lightly grease a loaf pan.

Combine ground beef, egg, breadcrumbs, milk, onion, ketchup, Worcestershire sauce, mustard, garlic powder, salt, and pepper in a large mixing bowl.

Scoop half of the meat mixture into the prepared loaf pan, pressing it down firmly.

Layer sliced cheddar cheese over the pressed meat mixture.

Top with remaining meat mixture, sealing the edges.

Spread ketchup evenly over the top.

Bake for 45 to 50 minutes until cooked through and thermometer reads 160°F.

Let the meatloaf rest for 10 minutes before slicing.