Preheat your oven to 350°F (175°C).

In a skillet over medium heat, sauté the chopped onion until translucent, about 5 minutes.

In a large mixing bowl, combine ground beef, breadcrumbs, sautéed onion, milk, 1/4 cup ketchup, eggs, salt, pepper, garlic powder, and Worcestershire sauce; mix gently to avoid overworking the meat.

Transfer the mixture into a loaf pan, shaping it into an even loaf.

Spread 1/2 cup of ketchup over the top of the meatloaf to create a glaze.

Bake in the preheated oven for about 1 hour, until cooked through.

Check the internal temperature with a meat thermometer; it should read 160°F (70°C).

Let the meatloaf rest in the pan for 10 minutes before slicing to allow juices to redistribute.