Mustard Vinaigrette 1/4 tsp. fresh tarragon, chopped 1 1/2 tbsp. sherry vinegar 1 1/2 tsp. Dijon mustard 2 tbsp. sour cream 6 tbsp. olive oil Salt In a small bowl, mix together vinegar, salt, mustard, tarragon, and sour cream. Whisk in olive oil.