Preheat your oven to 350°F (175°C).

In a large mixing bowl, combine the ground beef, breadcrumbs, milk, chopped onion, eggs, salt, and pepper. Mix gently to combine.

Transfer the meat mixture onto a baking dish and shape it into a loaf approximately 2-3 inches high.

In a separate bowl, mix together ketchup, brown sugar, and Worcestershire sauce until smooth and well-combined. Spread it evenly over the top of the shaped meatloaf.

Place the meatloaf in the oven and bake for about 1 hour until it registers an internal temperature of 160°F (70°C).

Let the meatloaf rest for 10 minutes before slicing.