Brown ground beef, onion and bacon until no pink remains. Drain well. Remove from heat and stir in bread crumbs, mustard, barbecue sauce, ketchup, Worcestershire and pepper. Place mixture in prepared pie crust.
In a small bowl, combine cheese, milk and egg. Spread over meat mixture.
Cover the edges of the pie crust with foil or a pie shield to prevent over browning. Bake 15 minutes, remove foil and bake an additional 15 minutes.