Ground Beef Special(Sloppy Joes)  
["2 lb. ground beef", "1 c. chopped onion", "2 tsp. prepared mustard", "3 tsp. salt", "1/8 tsp. pepper", "2 (8 oz.) cans tomato sauce", "2 Tbsp. vinegar"]
["Brown meat and onion; drain.", "Add all other ingredients. Simmer 20 minutes."]
["ground beef", "onion", "mustard", "salt", "pepper", "tomato sauce", "vinegar"]