1 (10 oz.) can condensed tomato soup
3/4 c. cider vinegar
1 tsp. salt
1/2 tsp. pepper
1 tsp. dry mustard
Dash of cayenne
5 tbsp. brown sugar
1 tsp. onion, finely chopped
1 1/2 c. salad oil

Combine all ingredients in a quart jar, shake vigorously and then chill. Shake again just before serving.