Seafood Gratin Recipe layers sweet shrimp, buttery scallops, and flaky white fish under a creamy, cheesy crust that bakes golden and spoonable. It suits anyone who wants coastal comfort without fuss, and it takes about 20 minutes prep and 25 minutes bake time for a total of 45 minutes. I picked up this move after a chilly New England trip, and it still beats my sweater at warming me up.
Why Seafood Gratin Recipe Is Worth It
Seafood Gratin Recipe delivers lush, briny flavor with a crisp, toasty top that begs for a spoon. The creamy Gruyère sauce hugs tender shrimp, scallops, and cod, so every bite feels rich but not heavy.
You can mix seafood based on what you have, which keeps it budget smart and pantry friendly. It works as a weeknight baked seafood casserole or a dinner party star, no tux required.
Ingredients You Need
- 1/2 lb large shrimp, peeled and deveined
- 1/2 lb sea scallops, halved if large
- 1/2 lb firm white fish such as cod or haddock, cut into 1-inch pieces
- 1 tsp kosher salt, divided
- 1/2 tsp black pepper
- 2 tbsp unsalted butter
- 1 tbsp olive oil
- 1 small shallot, minced (or 1/4 cup minced yellow onion)
- 2 garlic cloves, minced (jarred works in a pinch)
- 3 tbsp all-purpose flour
- 1 cup whole milk
- 1/2 cup seafood stock or clam juice (boxed stock or Better Than Bouillon seafood base works)
- 1/4 cup dry white wine, optional, or use more stock
- 1 tsp Dijon mustard
- 1 tsp lemon zest
- Pinch cayenne or 1/2 tsp Old Bay
- 1 cup grated Gruyère cheese (pre-shredded works, but grate your own for best melt)
- 1/2 cup grated Parmesan, divided
Topping
- 1 cup panko breadcrumbs
- 2 tbsp melted butter
- 2 tbsp grated Parmesan
- 1 tbsp chopped parsley
- 1/2 tsp sweet paprika
- Pinch kosher salt
Optional finishers
- Chopped chives
- Lemon wedges
Pantry shortcuts and notes
- Use frozen shrimp and scallops that you thaw and pat dry well.
- Swap cod with halibut, pollock, or salmon.
- Use half-and-half for a richer sauce or 2 percent milk for lighter.
- Gluten-free folks can use a 1:1 GF flour and GF panko.
Equipment
- 10-inch skillet or saucepan
- Whisk and wooden spoon
- Paper towels
- 2-quart baking dish
- Microplane for zest
Quick Tips & substitutions
- Dry the seafood thoroughly so the sauce stays thick and the topping stays crisp.
- Salt the seafood lightly before saucing to season from the inside out.
- Keep the heat moderate when making the roux so the flour cooks but does not brown.
- Pull the pan off heat before adding Gruyère to prevent grainy sauce.
- No wine on hand? Use extra stock plus a squeeze of lemon for brightness.
- Want extra crunch? Mix panko with crushed butter crackers.
- Sensitive to dairy? Use lactose-free milk and a lactose-free melting cheese.
- Cooking for two? Halve everything and use an 8-inch dish.
How to Make Seafood Gratin
- Prep: 20 minutes
- Cook: 25 minutes
- Total: 45 minutes
- Heat the oven to 400°F and butter a 2-quart baking dish.
- Pat shrimp, scallops, and fish dry with paper towels. Season with 1/2 tsp salt and the black pepper.
- Warm a skillet over medium heat. Add butter and olive oil, then sauté the shallot for 2 minutes until translucent. Stir in garlic for 30 seconds.
- Sprinkle in the flour and stir for 1 minute to form a smooth paste.
- Whisk in milk, then the stock and wine. Bring to a gentle simmer and cook 3 to 4 minutes until the sauce lightly coats the back of a spoon.
- Stir in Dijon, lemon zest, cayenne or Old Bay, and the remaining 1/2 tsp salt. Take the pan off heat and stir in Gruyère and 1/4 cup Parmesan until smooth.
- Fold the seasoned seafood into the warm sauce. Coat everything evenly without breaking the fish.
- Spoon the mixture into the baking dish. In a bowl, combine panko, melted butter, remaining 1/4 cup Parmesan, parsley, paprika, and a pinch of salt. Sprinkle the topping evenly.
- Bake for 18 to 22 minutes until the sauce bubbles at the edges and the seafood turns opaque. If you want deeper color, broil for 1 to 2 minutes while you watch closely.
- Rest the gratin for 5 minutes so it sets slightly. Finish with chives and serve with lemon wedges.
Variations
- Lobster twist: Fold in 1 cup chopped cooked lobster and reduce shrimp to 1/4 lb.
- Mushroom boost: Sauté 8 oz sliced cremini in butter and add to the sauce for earthy depth.
- Spinach version: Stir in 2 cups baby spinach until it wilts in the hot sauce.
- Spicy gratin: Add 1 tsp Calabrian chili paste or extra cayenne for a slow burn.
- Herb-forward: Swap parsley with tarragon and chives for a classic French vibe.
Ways to Serve Seafood Gratin
- Spoon over buttered noodles or garlic mashed potatoes.
- Serve with crusty bread or baguette to scoop up the creamy sauce.
- Pair with a crisp green salad with lemon vinaigrette.
- Add roasted asparagus, green beans, or broccolini on the side.
Storage
Cool leftovers to room temp within 30 minutes, then cover and refrigerate for up to 3 days. Reheat covered at 350°F until hot and bubbly, then uncover for 3 to 5 minutes to re-crisp the topping. You can reheat gently in a skillet with a splash of stock, though the topping softens. Skip freezing since cream sauces and seafood can turn grainy after thawing.
Seafood Gratin Recipe
Ingredients
Instructions
- Preheat the oven to 375°F (190°C).
- Melt butter in a saucepan over medium heat. Add garlic and sauté until fragrant.
- Whisk in flour and cook for 1-2 minutes to make a roux.
- Gradually add milk, whisking continuously until thickened.
- Season with salt and pepper and remove from heat.
- Combine seafood with the sauce, then transfer to a gratin dish.
- Top with Parmesan, Gruyere, and breadcrumbs.
- Bake for 20-25 minutes until golden and bubbly.
- Garnish with fresh parsley before serving.