Creamy Seafood Gratin with Scallops Shrimp

Creamy Seafood Gratin with Scallops Shrimp tastes rich, buttery, and cheesy with tender bites of seafood tucked into a silky sauce and topped with a golden crust. It suits cozy date nights, small dinner parties, or a weeknight treat, and you can finish it in about 45 minutes. I first made a version of this on a Tuesday when I felt fancy in sweatpants, and it instantly joined my regular rotation.

Why Choose This Creamy Seafood Gratin with Scallops Shrimp

This seafood gratin gives you restaurant-level flavor without complicated steps. You get sweet scallops, juicy shrimp, and a creamy garlic sauce under a crisp, cheesy breadcrumb topping that feels indulgent but still weeknight-manageable.

You also control the ingredients, so you skip mystery sauces and heavy salt from store-bought options. The recipe uses simple pantry items like broth, butter, and cheese, so you build big flavor with things you probably already own.

“This Creamy Seafood Gratin with Scallops Shrimp tastes like a fancy coastal restaurant special but comes together in my tiny kitchen without stress. ★★★★★”

Ingredients You’ll Need

Seafood

• Large sea scallops
  • About 12 ounces
  • Pat them very dry so they brown nicely
• Large shrimp
  • About 12 ounces, peeled and deveined
  • Tail on or off both work; I usually remove tails for easier eating

You can use frozen seafood. Thaw it in the fridge overnight or in a bowl of cold water, then dry it very well with paper towels.

Sauce base

• Unsalted butter
  • I like Kerrygold or any good quality butter for richer flavor
• Olive oil
  • Use a neutral, everyday bottle; no need for fancy finishing oil
• All-purpose flour
  • Thickens the sauce
• Garlic
  • Fresh cloves taste best; jarred minced garlic works in a pinch
• Shallot or yellow onion, finely minced
• Seafood stock or low-sodium chicken broth
  • Boxed broth works fine; choose low-sodium so you control the salt
• Heavy cream
  • Do not swap with milk, or the sauce can break and taste thin
• Dijon mustard
  • Adds gentle tang and depth; it will not taste like mustard
• Lemon juice
  • Fresh gives the best brightness; bottled works if that is what you have
• Salt and black pepper

Cheese and topping

• Gruyère cheese, shredded
  • Melts beautifully and brings nutty flavor
  • You can sub Swiss cheese if Gruyère costs too much or you cannot find it
• Parmesan cheese, finely grated
  • Adds salty, savory punch
• Panko breadcrumbs
  • Stay extra crisp; regular breadcrumbs also work, just a bit denser
• Fresh parsley, chopped
  • Optional but adds color and freshness
• Paprika
  • Adds color and a mild smoky note

Optional flavor boosters

• A pinch of red pepper flakes for gentle heat
• A small splash of fish sauce for deeper seafood flavor
• A little Old Bay or seafood seasoning blend

Equipment

• 10 to 12 inch oven-safe skillet or a medium baking dish (about 2 quart)
• Medium saucepan
• Cutting board and sharp knife
• Whisk
• Mixing bowls
• Measuring cups and spoons
• Paper towels to dry the seafood

Tips & Tricks

• Dry the scallops and shrimp very well so they brown nicely and do not steam.
• Use high heat to sear the scallops quickly and keep them tender.
• Do not overcook the seafood in the pan; let the oven finish the job.
• Warm the broth slightly so it blends into the roux without clumping.
• Add the cream slowly while you whisk to keep the sauce silky.
• Taste the sauce before you add cheese and adjust salt and lemon.
• Shred cheese from a block; bagged shreds contain starch that can make the sauce grainy.
• Spread the seafood in a single layer in the baking dish so it cooks evenly.
• Broil at the end for a minute or two if you want extra color on the topping.
• Let the gratin rest 5 to 10 minutes before serving so it thickens slightly.

How to Make Creamy Seafood Gratin with Scallops Shrimp

Prep the seafood and oven

1. Preheat your oven to 400°F.
2. Pat the scallops and shrimp very dry with paper towels.
3. Season both lightly with salt and pepper on all sides.
4. If the scallops look very thick, slice them in half horizontally so they match the shrimp size.

Sear the scallops and shrimp

1. Heat a large oven-safe skillet over medium high heat.
2. Add a little olive oil and a small knob of butter.
3. When the fat shimmers and smells nutty, place the scallops in the pan in a single layer.
4. Sear them 1 to 2 minutes per side until they develop a golden crust but stay slightly undercooked inside.
5. Transfer the scallops to a plate.
6. Add the shrimp to the same skillet and cook 1 to 2 minutes total until they just start to turn pink.
7. Move the shrimp to the plate with the scallops. They will finish cooking in the oven.

Build the creamy sauce

1. Lower the heat to medium and add a bit more butter if the pan looks dry.
2. Add the minced shallot or onion and cook 2 to 3 minutes until it softens and turns translucent.
3. Stir in the garlic and cook about 30 seconds until fragrant.
4. Sprinkle the flour over the mixture and stir constantly for 1 to 2 minutes to form a roux.
5. Slowly pour in the warm seafood stock or broth while you whisk, smoothing out any lumps.
6. Let the mixture simmer a few minutes until it thickens slightly.
7. Pour in the heavy cream and whisk until the sauce looks smooth and creamy.
8. Stir in Dijon mustard, a squeeze of lemon juice, and any optional seasonings.
9. Taste and adjust with more salt, pepper, or lemon as needed.

Add cheese and seafood

1. Turn the heat to low.
2. Add the shredded Gruyère and a bit of Parmesan to the sauce.
3. Stir until the cheese melts and the sauce turns glossy and thick.
4. Nestle the scallops and shrimp into the sauce in an even layer.
5. Spoon some sauce over the top so every piece of seafood gets coated.

Mix and add the topping

1. In a small bowl, combine panko breadcrumbs, the rest of the Parmesan, a pinch of paprika, and chopped parsley.
2. Drizzle in a little olive oil or melted butter and toss until the crumbs feel lightly coated.
3. Sprinkle the breadcrumb mixture evenly over the seafood and sauce.

Bake the gratin

1. Place the skillet or baking dish in the preheated oven.
2. Bake 10 to 15 minutes until the topping turns golden and the sauce bubbles around the edges.
3. If you want deeper color, switch to broil for 1 to 2 minutes and watch closely so it does not burn.
4. Remove from the oven and let the Creamy Seafood Gratin with Scallops Shrimp rest 5 to 10 minutes before serving.

What to Serve with it?

This Creamy Seafood Gratin with Scallops Shrimp pairs beautifully with a simple green salad dressed with lemon and olive oil. You can add steamed green beans, roasted asparagus, or sautéed spinach to balance the richness. Serve it with crusty bread, garlic toast, or fluffy white rice to soak up the sauce. If you want a drink, pour sparkling water with citrus slices or a light herbal iced tea.

Storage Options

• Cool leftovers to room temperature, then store them in an airtight container in the fridge for up to 2 days.
• Reheat gently in a 325°F oven, covered, until hot in the center, then uncover for a few minutes to re-crisp the topping.
• You can freeze portions in freezer-safe containers for up to 1 month, though the sauce may lose a bit of creaminess.
• Thaw frozen gratin overnight in the fridge and reheat in the oven; avoid the microwave if possible so the seafood stays tender.

Creamy Seafood Gratin with Scallops and Shrimp

Creamy Seafood Gratin with Scallops and Shrimp is a rich, comforting baked seafood dish with a velvety cream sauce and a crisp golden topping.

Pin Recipe

Prep Time 20 minutes mins

Cook Time 25 minutes mins

Total Time 45 minutes mins

Servings: 4

Course: Dinner

Cuisine: American

Ingredients Method Notes

Ingredients

  

• 8 ounces large sea scallops, patted dry
• 8 ounces large shrimp, peeled and deveined
• 2 tablespoons unsalted butter
• 1 tablespoon olive oil
• 2 cloves garlic, minced
• 1 small shallot, finely chopped
• 1/2 cup dry white wine
• 3/4 cup heavy cream
• 1/2 cup whole milk
• 1 tablespoon all-purpose flour
• 1/2 cup grated Parmesan cheese
• 1/4 cup grated Gruyère or Swiss cheese
• 1/4 teaspoon paprika
• 1/4 teaspoon black pepper
• 1/2 teaspoon fine sea salt
• 1/2 cup panko breadcrumbs
• 1 tablespoon melted butter
• 1 tablespoon fresh parsley, chopped
• 1 teaspoon lemon zest

Method

 

1. Preheat the oven to 400°F (200°C). Lightly butter a shallow 1 1/2- to 2-quart baking dish or 4 individual gratin dishes.
2. Pat the scallops and shrimp dry with paper towels and season lightly with salt and black pepper.
3. Heat 1 tablespoon butter and the olive oil in a large skillet over medium-high heat. Add the scallops and sear 1–2 minutes per side until lightly golden but not fully cooked. Transfer to a plate.
4. Add the shrimp to the skillet and cook 1–2 minutes, just until pink on the outside. Transfer to the plate with the scallops.
5. Reduce the heat to medium. Add the remaining 1 tablespoon butter to the skillet along with the shallot and garlic. Sauté 1–2 minutes until softened and fragrant.
6. Sprinkle the flour over the shallot mixture and cook, stirring constantly, for 1 minute to form a paste.
7. Slowly whisk in the white wine, scraping up any browned bits from the pan. Simmer 1–2 minutes to reduce slightly.
8. Gradually whisk in the heavy cream and milk. Cook 3–4 minutes, stirring often, until the sauce thickens enough to coat the back of a spoon.
9. Stir in the Parmesan, Gruyère, paprika, and a pinch more salt and pepper to taste. Remove from the heat.
10. Arrange the scallops and shrimp in the prepared baking dish. Pour the warm cream sauce evenly over the seafood.
11. In a small bowl, combine the panko breadcrumbs with the melted butter, parsley, and lemon zest. Sprinkle the mixture evenly over the top of the gratin.
12. Bake for 12–15 minutes, or until the top is golden brown and the sauce is bubbling around the edges.
13. Let the gratin rest for 5 minutes before serving to allow the sauce to thicken slightly. Serve hot with crusty bread, rice, or a simple green salad.

Notes

Nutrition Information
Approximate per serving (1/4 of recipe): 510 calories; fat 33 g; saturated fat 17 g; carbohydrates 17 g; fiber 1 g; sugars 4 g; protein 32 g; sodium 780 mg. Values will vary based on brands, add-ins, and portion size.