1 c. mayonnaise
2 tbsp. vinegar
1 tbsp. prepared mustard
1 tsp. sugar
1 tsp. salt
1/4 tsp. black pepper
8 oz. elbow macaroni, cooked and drained
1 c. chopped celery
1 c. green peppers, chopped
1/4 c. chopped onion

Combine first six ingredients. Mix with remaining ingredients. Cover and chill.