Dipping Sauce for Crab 2 tablespoons water 2 tablespoons fish sauce 1/4 cup white wine vinegar or rice vinegar 2 tablespoons sugar (or to taste) 2 tablespoons chopped green onion 2 tablespoons chopped cilantro 1 tablespoons lime juice 1 teaspoon lime zest optional: 1 teaspoon minced mint or lemon verbena 1. Mix all ingredients together until sugar had dissolved. Serve as a dipping sauce with fresh cooked Dungeness crab.