3 tablespoons bottled capers, drained
1/2 cup packed fresh parsley leaves (preferably Italian flat-leaf)
1/3 cup virgin olive oil
2 tablespoons chopped shallots or onion
1 teaspoon Dijon mustard
1 clove of garlic, chopped
1 tablespoon balsamic or red wine vinegar
Place all ingredients except vinegar in a food processor or blender and process until finely chopped. Pour into a serving dish or gravy boat. Refrigerate until ready to use. Before serving, bring to room temperature and whisk in vinegar.
Serve with fish.
Makes 2/3 cup.