Jacob Clark, chef at Maison Premiere restaurant and bar in Brooklyn, learned to make gumbo from his Louisiana-born father. Today, Clark’s team at the restaurant makes gallons of shrimp-and-lobster stock for his gumbo, but he suggests home cooks just use the reserved shrimp shells and heads from the recipe fortify store-bought fish stock. (He also serves his with a half of a steamed blue crab cracked into every bowl.) To make the stock: Toast the shrimp shells in a 375°F oven until toasty, red, and crisp, then add them to the cold stock. Simmer gently until the broth is rich and flavorful, about 30 minutes, then strain.