1 can condensed cream of mushroom sup
1 sm. slice onion, chopped
1/4 c. grated Parmesan cheese
3 tbsp. Worcestershire sauce
2 tbsp. vinegar
1/2 tsp. paprika
1/2 c. salad oil
1/8 tsp. pepper

Blend in blender all but oil at low speed. Add oil gradually. Put into container and refrigerate. Makes about 2 cups.