Chop onion, crumble hamburger and put into medium size saucepan in which 1 or 2 tablespoons of shortening has been heated. Stir over low heat until the hamburger is slightly brown and the onion tender. Add chili sauce, vinegar, mustard, Worcestershire sauce, sugar, salt and pepper. Cover and simmer over low heat for 1 hour. Serve hot on split rolls.
Servings: