Preheat oven to 350°F. Add ground beef, onion, egg, bread, 1 tablespoon tomato sauce, and 1 tablespoon ketchup to Mix n Blend II blender jar and secure lid. Press "Pulse" 5–8 times or until ingredients are incorporated. Transfer mixture to 9" x 5" loaf pan. Bake for 45 minutes. Meanwhile, add 1 cup tomato sauce, 2 tablespoons ketchup, dry mustard, vinegar, Worcestershire sauce, and sugar to clean jar and secure lid. Select "Sauces." Drain excess fat from meatloaf, and pour sauce over top. Return to oven to bake 45 minutes more or until done.