Chef John Currence of City Grocery Restaurant Group in Oxford, Mississippi, uses a sauce ravigote (from the French ravigoter, “to reinvigorate”) to lend a bright and tangy note to this chilled seafood salad. In his distinctly Gulf Coast take, seasoned Creole mustard provides a punchy kick alongside the milder Dijon, but any good whole-grain mustard will work. We prefer crawfish tails for their sweetness, but you can swap in your favorite cooked shellfish, such as crabmeat, shrimp, lobster, or even fried oysters. You can prepare your own mustard to adjust the flavor to your liking.