1/2 lb Regular ground beef
1/3 c Tomato puree
1/4 c Onion, chopped
2 tb Vinegar
2 ts Sugar
1/4 ts Dry mustard
1 ds Pepper
2 Hamburger rolls

Cook beef until lightly browned. Drain fat. Mix in remaining ingredients except hamburger rolls. Cover and cook over low heat for 20 minutes to blend flavors. Stir occasionally. Spoon mixture onto bottom halves of rolls (about 1/2 cup per sandwich). Cover with top halves.