This is a favorite at our house. Dallin actually made it this time, it's so easy and so yummy.
1/4 cup milk
1/4 cup dry bread crumbs
1 envelope brown gravy mix, divided
1 teaspoon dried minced onion
1 pound lean ground beef
1/2 cup water
1 tablespoon prepared mustard (I omit this)
In a bowl, whisk the egg and milk. Add bread crumbs, 1 Tbsp gravy mix and onion. Crumble beef over mixture and mix well. Shape into 3-5 patties about 3/4 inches thick. Broil 3-4 inches from the heat for 6-7 minutes on each side or until meat is no longer pink and a meat thermometer reads 160.
Place remaining gravy mix in a small saucepan; stir in the water and mustard. Bring to a boil, cook and stir until thickened. Serve gravy over the beef patties.