Mary's Meatloaf

Preheat oven to 350 degrees F (175 degrees C).
In a large bowl, thoroughly mix ground beef, onion, salt, pepper and garlic powder. Mix in bread, milk, egg, 2 tablespoons mustard and 1/4 cup ketchup.
Press the meat mixture into a 9x5 inch loaf pan. In a small bowl, stir together remaining mustard, ketchup and brown sugar; pour on top of the meat loaf.
Bake in preheated oven for 2 hours.