Preheat your oven to 375°F (190°C). Lightly grease a 9x13 inch baking dish.
In a large bowl, combine the ground beef, breadcrumbs, milk, egg, chopped onion, 2 tablespoons of ketchup, Worcestershire sauce, salt, and pepper. Mix gently with your hands until just combined. Be careful not to overmix.
Press the meatloaf mixture evenly into the prepared baking dish.
In a small bowl, whisk together the glaze ingredients: 0.5 cup ketchup, brown sugar, and Dijon mustard.
Spread the glaze evenly over the top of the meatloaf mixture.
Bake for 45-55 minutes, or until the internal temperature of the meatloaf reaches 160°F (71°C) and the glaze is slightly caramelized.
Let the meatloaf rest for 10 minutes before slicing and serving.
Notes
Serve with mashed potatoes or your favorite side dishes.