Scallop and Shrimp Gratin

There’s something incredibly luxurious about a bubbling seafood gratin fresh from the oven. The cream is hot and gently thickened, the top is golden and crisp, and underneath, tender scallops and juicy shrimp rest in a velvety garlic sauce. Every spoonful feels like the best part of a restaurant meal—rich, comforting, and deeply satisfying.

This Scallop and Shrimp Gratin gives you all of that elegance with surprisingly simple steps. It’s the kind of dish that looks impressive in individual ramekins or a pretty baking dish, yet it’s easy enough to prepare for a cozy weekend dinner at home. The sweetness of scallops, the delicate flavor of shrimp, and the earthiness of sautéed mushrooms all come together under a blanket of cream, cheese, and crisp breadcrumbs.

Unlike complicated seafood recipes that demand perfect pan-searing or precise timing, this gratin is forgiving. The oven does most of the work, gently cooking the seafood in the sauce until it’s just done—tender, moist, and infused with flavor. A simple salad and some crusty bread are all you need to turn it into a complete, memorable meal.

Core Ingredients for Making the Recipe

To build layers of flavor in this gratin, you’ll start with aromatic shallots and garlic, add mushrooms for depth, then fold in succulent scallops and shrimp with a creamy, lightly cheesy sauce. The final topping gives the dish its irresistible golden crust.

Here’s what you’ll need:

Seafood & Vegetables

300 g scallops
- Small or medium sea scallops are ideal; if they’re very large, you can cut them in half horizontally.
200 g peeled shrimp
- Medium shrimp, cleaned and deveined.
150 g button mushrooms, cleaned and sliced
2 finely chopped shallots
1 clove garlic, chopped (you can add a second clove if you love garlic)

For the Creamy Gratin Sauce

2 tablespoons unsalted butter
1 tablespoon olive oil
2 tablespoons all-purpose flour
120 ml (½ cup) dry white wine (optional but highly recommended)
250 ml (1 cup) fish stock, seafood stock, or light chicken broth
200 ml (about ¾–1 cup) heavy cream or crème fraîche
½ teaspoon Dijon mustard
½ teaspoon salt, plus more to taste
¼ teaspoon freshly ground black pepper
¼ teaspoon paprika (sweet or smoked)
¼ teaspoon dried thyme or 1 teaspoon fresh thyme leaves
Pinch of nutmeg (optional, but nice with cream)
Juice of ½ small lemon (about 1 tablespoon), plus more for finishing if needed

For the Gratin Topping

40 g (about ½ cup) fresh breadcrumbs or panko
40 g (about ½ cup loosely packed) grated Parmesan cheese
30 g (¼ cup) grated Gruyère or Emmental (for extra melting richness)
1 tablespoon melted butter or olive oil
1–2 tablespoons chopped fresh parsley

To Finish & Serve

Extra chopped parsley or chives
Lemon wedges
Crusty bread, baguette slices, or toasted brioche
Simple green salad, rice, or mashed potatoes as a side (optional)

Step-by-Step

Guide to Making Scallop and Shrimp Gratin

1. Prepare the Seafood

Pat dry and season

Gently pat the scallops and shrimp dry with paper towels. Extra moisture can dilute the sauce and prevent browning.
Lightly season the seafood with a pinch of salt, pepper, and a few drops of lemon juice. Set aside while you prepare the sauce.

If your scallops have a small, tough side muscle attached, peel it off and discard—it’s edible but chewy.

2. Sauté the Mushrooms, Shallots, and Garlic

Heat the pan
- In a large skillet, heat 1 tablespoon olive oil and 1 tablespoon butter over medium heat.
Cook the mushrooms
- Add the sliced button mushrooms in a single layer.
- Sprinkle with a small pinch of salt to encourage them to release their moisture.
- Cook for 5–7 minutes, stirring occasionally, until the mushrooms are browned and any liquid has evaporated.
Add shallots and garlic
- Add the finely chopped shallots to the pan and cook for 2–3 minutes, until soft and translucent.
- Stir in the chopped garlic and cook for about 30–60 seconds, just until fragrant.
- Be careful not to brown the garlic too much—it can turn bitter.

At this point, the mixture should be fragrant and slightly caramelized, forming the flavorful base of your gratin.

3. Make the Creamy Gratin Sauce

Create a roux
- Sprinkle 2 tablespoons flour over the mushroom-shallot mixture.
- Stir well so the flour coats the vegetables and absorbs the fat.
- Cook for about 1–2 minutes, stirring all the time. This step cooks away the raw flour taste.
Deglaze with wine (optional, but delicious)
- Slowly pour in the white wine while stirring, scraping up any browned bits from the bottom of the pan.
- Let it simmer for 1–2 minutes to reduce slightly and cook off the alcohol.
Add the stock
- Gradually add the fish or chicken stock while whisking or stirring constantly to avoid lumps.
- Bring to a soft simmer; the mixture should begin to thicken.
Stir in the cream and seasonings
- Lower the heat and add the heavy cream or crème fraîche.
- Stir in the Dijon mustard, thyme, paprika, nutmeg (if using), salt, and pepper.
- Simmer gently for 3–5 minutes, until the sauce is thick enough to coat the back of a spoon.
Taste and balance
- Taste the sauce and adjust seasoning.
- Add the lemon juice to brighten it—the goal is a rich, creamy sauce with just enough acidity to keep it from feeling heavy.
- If it’s too thick, thin with a splash of stock or cream; if too thin, let it simmer a little longer.

Turn off the heat and let the sauce cool for a few minutes. It will thicken slightly as it stands.

4. Add the Scallops and Shrimp

You want the seafood to cook gently in the oven, not boil in the pan, so it’s best added right before baking.

Fold the seafood into the sauce
- Add the scallops and shrimp directly into the warm sauce.
- Gently fold them through, making sure they’re evenly distributed and fully coated.
Arrange in baking dishes
- Spoon the mixture into individual gratin dishes, ramekins, or one medium baking dish (about 1½–2 liters capacity).
- Avoid overcrowding; the seafood should sit in a single layer or just slightly overlapping for even cooking.

5. Prepare the Gratin Topping

The topping is what gives this dish its signature golden, crunchy layer.

Mix breadcrumbs and cheeses
- In a small bowl, combine the breadcrumbs, Parmesan, and Gruyère.
Add butter and herbs
- Stir in the melted butter (or olive oil) until the mixture is evenly moistened—this helps the crumbs crisp in the oven.
- Fold in the chopped parsley for color and freshness.
Top the gratin
- Sprinkle the topping evenly over each dish, fully covering the surface for maximum crunch.

6. Bake Until Bubbling and Golden

Preheat the oven
- If you haven’t already, preheat your oven to 375°F (190°C).
Bake
- Place the gratins on a baking tray to catch any drips.
- Bake for about 15–20 minutes, until the sauce is bubbling at the edges and the topping is golden.
- If your dishes are shallow or the seafood pieces are small, check at 12–15 minutes; seafood cooks quickly.
Optional broil
- If the topping isn’t quite browned enough, you can switch the oven to broil (grill) for 1–2 minutes.
- Watch carefully so it doesn’t burn.
Rest briefly
- Remove the gratins from the oven and let them rest for 5 minutes. The sauce will settle and thicken slightly, and the seafood will finish cooking gently in the residual heat.

Flavor Variations and Creative Twists

One of the pleasures of a recipe like this is how flexible it is. Once you master the base, you can adjust ingredients and seasonings to fit your taste, the season, or what you have in the fridge.

1. Herbed Lemon Gratin

For a brighter, fresher version:

Use more lemon zest along with the juice.
Add finely chopped fresh herbs like tarragon, chives, and parsley to the sauce.
Reduce the cheese in the topping slightly so the herbs and citrus shine.
Serve with extra lemon wedges so each person can add more brightness to their plate.

2. Garlic-Parmesan Only (No Mushrooms)

If you prefer a simpler profile without mushrooms:

Omit the mushrooms and increase the shallots slightly.
Add an extra clove of garlic for a more pronounced garlicky flavor.
Use more Parmesan in the topping and a bit stirred into the sauce for an ultra-cheesy gratin.

3. Mediterranean-Style Gratin

To give this dish a hint of the Mediterranean:

Add a handful of chopped sun-dried tomatoes to the sauce.
Sprinkle in a bit of oregano or basil instead of thyme.
Use crumbled feta mixed with the breadcrumbs in place of Gruyère.
Finish with a drizzle of good olive oil and some chopped olives on top after baking.

4. Spicy Seafood Gratin

For a gentle kick:

Add ¼–½ teaspoon chili flakes or a pinch of cayenne pepper to the sauce.
Finish the dish with a drizzle of chili oil or sprinkle of extra chili flakes before serving.
This variation pairs especially well with crusty bread and a crisp salad.

5. Extra-Luxurious Gratin

When you really want to spoil yourself or impress guests:

Replace part of the shrimp with lobster or crab meat.
Use crème fraîche instead of cream.
Mix in a splash of brandy or cognac with the wine when deglazing for a rich, restaurant-style depth.
Top with a blend of Parmesan and aged Gruyère for intense cheesy flavor.

How to Serve Scallop and Shrimp Gratin

This gratin is rich and flavorful, so it benefits from simple sides that complement without competing.

Serving Suggestions

Crusty bread or baguette
- Essential for soaking up every drop of sauce. Toast slices lightly for extra crunch.
Light green salad
- A salad of mixed greens with a lemony vinaigrette cuts through the richness beautifully.
- Add shaved fennel or cucumber for extra freshness.
Rice, mashed potatoes, or pasta
- For a more substantial meal, serve the gratin over fluffy rice, creamy mashed potatoes, or buttered pasta.
- Spoon some of the sauce over the starch for a complete, comforting plate.
Wine pairing
- A crisp white wine like Sauvignon Blanc, Pinot Grigio, or a lightly oaked Chardonnay pairs wonderfully with the creamy seafood.

Serve the gratin directly in individual dishes for a bistro-style presentation, or bring a large, bubbling casserole to the table and let everyone serve themselves.

Tips & Helpful Notes

Choosing the Seafood

Scallops
- Use fresh if possible, or good-quality frozen scallops thawed in the fridge.
- Pat them very dry; excess moisture can water down the sauce.
Shrimp
- Medium-size shrimp work best: big enough to stay juicy, small enough to eat easily with a spoon.
- Frozen shrimp are often excellent; just thaw and dry well.

Avoid Overcooking

Seafood cooks quickly; overcooking leads to tough scallops and rubbery shrimp.

The seafood goes into the oven in a warm but not boiling sauce.
A bake time of 15–20 minutes is usually enough.
Remember that residual heat continues cooking after you take the gratin out, so it’s better to stop when the seafood is just opaque rather than very firm.

Adjusting the Sauce

If the sauce seems too thin before adding seafood, simmer it a little longer. It should be thick enough to coat a spoon but still pourable.
If it’s too thick, add a splash of stock or cream.

Seasoning Wisely

Seafood is delicate; you want enough salt to bring out its sweetness without overpowering it.
Taste the sauce multiple times—before adding cream, after adding cream, and again after lemon juice—to keep the balance right.

Make-Ahead Tips

You can prepare the mushroom-shallot sauce a few hours ahead and keep it in the fridge.
When ready to bake, gently reheat the sauce so it’s warm (but not boiling), fold in the scallops and shrimp, add the topping, and bake.
It’s best to cook the seafood just before serving rather than baking the entire gratin far in advance, to maintain optimal texture.

Final Thoughts

Scallop and Shrimp Gratin is one of those dishes that feels like a little celebration every time you make it. It’s not complicated, but the combination of tender seafood, savory mushrooms, and a bubbling, creamy sauce crowned with golden crumbs gives it an air of quiet luxury.

It’s the kind of recipe that works for many occasions:

A cozy romantic dinner at home with candles and a glass of wine.
A special weekend meal to spoil your family.
An elegant starter for a multi-course menu, served in small individual ramekins.

Once you’ve made it once, you’ll see how easy it is to adjust—more herbs, a touch more lemon, maybe a little extra cheese if that’s what you love. It’s a recipe worth coming back to whenever you want something comforting, impressive, and full of seafood flavor without spending all day in the kitchen.

FAQ

Can I use frozen scallops and shrimp?
Yes. Frozen seafood works very well in this recipe. Thaw completely in the refrigerator, then pat dry thoroughly with paper towels before using. Excess water is the enemy of a thick, rich sauce.

Do I have to use white wine?
No, but it adds wonderful depth and a gentle acidity. If you prefer not to use alcohol, simply skip the wine and deglaze the pan with a bit of extra stock plus a teaspoon of lemon juice later for brightness.

Can I make this gratin without mushrooms?
Absolutely. Just omit the mushrooms and proceed with the shallots and garlic. You may want to increase the amount of seafood slightly (e.g., more shrimp) to keep the dish hearty, or add another vegetable like thinly sliced leeks.

What kind of cheese is best for the topping?
Parmesan adds a sharp, salty note, while Gruyère or Emmental melts beautifully and gives a nutty richness. You can use just Parmesan if that’s what you have, or substitute with other good melting cheeses like Comté, mild cheddar, or Asiago.

Can I make this dish in advance and reheat it?
It’s best enjoyed freshly baked. If you bake it completely in advance and reheat, the seafood can overcook and become rubbery. Instead, prepare the sauce ahead and assemble with raw seafood just before baking, so everything cooks perfectly in one go.

Is there a lighter version of this gratin?
Yes. You can:

Use half cream and half whole milk or evaporated milk.
Reduce the cheese and breadcrumbs slightly.
Add more vegetables (like spinach or leeks) to stretch the sauce without more cream.

The dish will still be creamy, just less rich.

Can I use other seafood?
Definitely. This recipe works well with chunks of firm white fish (like cod or haddock), crab meat, or even small pieces of salmon. Just keep the total amount of seafood around 500 g and cut everything into similar-sized pieces for even cooking.

Enjoy creating your Scallop and Shrimp Gratin—and enjoy even more that first spoonful of golden, bubbling, seafood perfection.