Preheat your oven to 350°F (175°C). Lightly grease a 9x5 inch loaf pan.
In a large mixing bowl, combine the ground beef, breadcrumbs, milk, chopped onion, chopped green bell pepper, beaten eggs, 2 tablespoons of Worcestershire sauce, 1 tablespoon of ketchup, salt, and pepper. Mix gently with your hands until just combined. Be careful not to overmix, as this can make the meatloaf tough.
Press the meat mixture evenly into the prepared loaf pan.
In a small bowl, whisk together the brown sugar, remaining ketchup (about 2-3 tablespoons), and Dijon mustard until smooth. This will be your glaze.
Spread the glaze evenly over the top of the meatloaf.
Bake for 60-75 minutes, or until the internal temperature reaches 160°F (71°C) and the glaze is caramelized and bubbly. If the glaze starts to brown too quickly, you can loosely tent the meatloaf with aluminum foil.
Once baked, let the meatloaf rest in the pan for about 10 minutes before slicing and serving. This allows the juices to redistribute, resulting in a more tender and flavorful meatloaf.