Mom'S Beef Barbecue
["1 medium onion, chopped", "1 lb. ground beef", "2 Tbsp. oil (optional)", "2 Tbsp. brown sugar", "2 Tbsp. vinegar", "4 Tbsp. lemon juice", "2 Tbsp. Worcestershire sauce", "1/2 tsp. prepared mustard", "1/2 c. catsup", "salt", "pepper"]
["Brown onion and ground beef in oil; drain.", "Add remaining ingredients.", "Heat over low flame.", "Serve on buns."]
["onion", "ground beef", "oil", "brown sugar", "vinegar", "lemon juice", "Worcestershire sauce", "mustard", "catsup", "salt", "pepper"]