Creamy Seafood Gratin with Scallops Shrimp tastes rich, briny, and cozy, with sweet seared scallops, juicy shrimp, and a cheesy golden crust. It suits date night or a small dinner party and takes about 45 minutes from start to finish. I baked this after a long shift once, and my sister asked for seconds before the dish even hit the trivet.
Creamy Seafood Gratin with Scallops Shrimp
Creamy Seafood Gratin with Scallops Shrimp stays simple because you build a quick cream sauce on the stove, then finish the seafood under heat in the oven. Store-bought clam juice, panko, and prepped shrimp speed things up without sacrificing flavor. The oven handles the bubbling and browning while you set the table.
Ingredients You Need
- Sea scallops, 12 ounces, patted very dry (use dry-packed scallops for best sear; avoid treated or “wet” scallops)
- Large shrimp, 12 ounces, peeled and deveined, tails off
- Kosher salt and black pepper
- Olive oil, 1 tablespoon
- Unsalted butter, 3 tablespoons, divided
- Shallot, 1 large, finely chopped
- Garlic, 3 cloves, minced
- All-purpose flour, 1 tablespoon (use cornstarch for gluten-free, 2 teaspoons mixed with stock)
- Dry white wine or dry vermouth, 1/2 cup
- Clam juice or seafood stock, 1/2 cup (pantry shortcut that adds briny depth)
- Heavy cream, 3/4 cup
- Dijon mustard, 1 teaspoon
- Lemon zest, 1 teaspoon, plus lemon wedges for serving
- Fresh thyme leaves, 1 teaspoon, or 1/2 teaspoon dried
- Gruyère, 3/4 cup shredded, lightly packed (block cheese melts smoother than pre-shredded)
- Parmesan, 1/3 cup finely grated, divided
- Panko breadcrumbs, 3/4 cup (use gluten-free panko if needed)
- Fresh parsley or chives, 2 tablespoons chopped
- Pinch of smoked paprika or cayenne, optional
Equipment
- 10-inch oven-safe skillet or sauté pan
- 1.5 to 2-quart shallow baking or gratin dish
- Small bowl for topping
- Whisk and spatula
How to Make Creamy Seafood Gratin with Scallops Shrimp
- Prep: 15 minutes
- Cook: 25 to 30 minutes
- Total: 40 to 45 minutes
- Preheat the oven to 425°F. Pat scallops and shrimp very dry, then season both with 3/4 teaspoon kosher salt and 1/2 teaspoon black pepper.
- Sear the seafood. Heat olive oil and 1 tablespoon butter in the skillet over medium-high. Add scallops in a single layer and sear 45 to 60 seconds per side, just to get light color. Transfer to a plate. Sear shrimp 30 to 45 seconds per side. Transfer to the same plate. You only want a quick kiss of heat here.
- Build the sauce. Lower heat to medium. Add remaining 2 tablespoons butter to the skillet. Stir in shallot and cook 2 minutes until translucent. Add garlic and cook 30 seconds. Sprinkle in flour and whisk for 30 seconds to make a blond roux.
- Deglaze and simmer. Pour in wine and whisk while it bubbles and reduces by half, 1 to 2 minutes. Add clam juice, then cream, Dijon, lemon zest, thyme, and a small pinch of salt and pepper. Simmer 2 to 3 minutes until the sauce lightly coats a spoon.
- Add the cheeses. Take the pan off heat. Stir in Gruyère and half the Parmesan until smooth. Taste and adjust seasoning. Stir in a pinch of smoked paprika or cayenne if you want a gentle kick.
- Assemble. Gently fold the scallops and shrimp into the sauce. Pour everything into the gratin dish.
- Make the topping. In a small bowl, mix panko, remaining Parmesan, parsley or chives, a pinch of salt, and 1 teaspoon olive oil or melted butter. Sprinkle evenly over the seafood.
- Bake 10 to 12 minutes until the sauce bubbles at the edges and the center reads 125 to 130°F for the seafood. Broil 1 to 2 minutes to brown the top. Let the gratin rest 5 minutes so the sauce settles. Squeeze lemon over the top and serve hot.
Tips & Common Mistakes
- Dry the seafood well to avoid a watery gratin.
- Use dry-packed scallops; treated scallops release excess liquid and taste bland.
- Sear quickly and pull early; the seafood finishes in the oven.
- Reduce the wine enough so the sauce tastes balanced, not boozy.
- Add cheese off heat to prevent a grainy sauce.
- Season lightly before baking; Parmesan adds salt.
- Keep the topping dry; too much butter turns it greasy instead of crisp.
- Use a shallow dish; a deep dish steams the topping and softens the crunch.
- Watch the broiler like a hawk; the crust can go from golden to charcoal in seconds.
- Rest the gratin 5 minutes so the sauce thickens and clings.
Variations I’ve Tried
- Lobster and crab mix: fold in 8 ounces cooked lobster meat and 4 ounces lump crab in place of shrimp.
- Fennel-leek version: sauté 1 cup thinly sliced fennel and 1 cup sliced leeks with the shallot for sweet, aromatic depth.
- Smoky cheddar swap: use half Gruyère and half smoked gouda or sharp white cheddar for a bolder crust.
- Old Bay twist: season the shrimp with 1 teaspoon Old Bay and skip the thyme.
- Low-carb topping: use crushed pork rinds in place of panko.
- Gluten-free: use cornstarch to thicken the sauce and gluten-free panko on top.
- No wine: use extra stock and a bigger splash of lemon juice for brightness.
How to Serve Creamy Seafood Gratin
Serve this seafood gratin with a crisp green salad and citrus vinaigrette to cut through the richness. Add warm crusty bread for dunking or spoon it over buttered rice or orzo. A chilled Sauvignon Blanc, Chablis, or a dry sparkling wine pairs beautifully.
Make-Ahead and Storage
Make the sauce and topping up to 24 hours ahead and keep them separate in the fridge. Sear the seafood just before baking for the best texture. If you must assemble in advance, chill the dish, then bake straight from cold at 375°F for a few extra minutes and finish under the broiler.
Store leftovers in an airtight container in the fridge for up to 2 days. Reheat at 325°F, covered for 10 minutes, then uncovered for 5 minutes to crisp the top. The freezer can dull seafood texture and split the sauce, so I skip it. If you freeze anyway, wrap tightly for up to 1 month and thaw in the fridge before a gentle reheat.
Nutrition Information
Approximate per serving for 6 servings: 520 calories; 33g protein; 34g fat; 17g carbs; 1g fiber; 980mg sodium. Numbers will vary based on cheese, cream, and salt levels.
Ingredients
Instructions
- Preheat oven to 375°F (190°C).
- In a saucepan, melt butter over medium heat. Stir in flour and cook for 1 minute.
- Gradually whisk in milk and heavy cream. Cook until thickened, about 5 minutes.
- Remove from heat, stir in Parmesan cheese, garlic powder, salt, and pepper.
- Add scallops and shrimp to the sauce and combine gently.
- Transfer mixture to a greased baking dish. Sprinkle breadcrumbs evenly on top.
- Bake for 20-25 minutes until golden and bubbly.
- Garnish with fresh parsley if desired and serve hot.