Name: Cheesy Scallop Gratin with Mushroom Béchamel Recipe
Prep time: 15 min
Cook time: 20 min
Total time: 35 min
Cuisine: French
Ingredients: 220g / 7 1/2 oz medium raw scallops; 1/4 tsp cooking salt / kosher salt; 30g / 2 tbsp unsalted butter; 1 eschalot (shallot), finely diced; 200g / 7 oz white mushrooms, diced 8mm / 1/4″; 2 tbsp plain flour (all-purpose); 1/2 cup hot milk (preferably full fat, but lite milk works too); 1/2 cup hot thickened cream (heavy cream or any other full fat cream); 1/4 tsp cooking salt / kosher salt; 1/8 tsp black pepper; 1 pinch ground nutmeg; 3/4 cup panko breadcrumbs; 50g / 3 tbsp unsalted butter, melted; 50g / 1/2 cup Gruyère cheese, shredded; 1/8 tsp cooking salt

Jump to Recipe· 4.4 from 3 reviews

If you’re craving a dish that feels effortlessly elegant and bursting with flavor, the Cheesy Scallop Gratin with Mushroom Béchamel Recipe is an absolute must-try. This classic French-inspired creation combines tender, sweet scallops topped with a luscious, creamy mushroom béchamel and a golden, crispy cheese crust that will have you savoring every bite. Perfect for a special dinner or to simply impress your loved ones, this gratin strikes the ideal balance between rich indulgence and comforting home-style cooking.

Ingredients You’ll Need

A white bowl filled with large, light yellow apple pieces as the bottom layer, topped with thick, creamy beige sauce with small brown mushroom chunks being poured over it from a large spoon held slightly above the bowl. In the background, there is a second white bowl filled with a similar creamy mushroom sauce. The scene is set on a white marbled surface. photo taken with an iphone --ar 4:5 --v 7

Gathering a handful of simple yet essential ingredients unlocks all the magic in this dish. Each element plays a crucial role — from tender scallops providing the star protein, to the creamy mushroom béchamel that lends richness and earthiness, and finally the crunchy, cheesy topping that brings texture and irresistible flavor.

220g / 7 1/2 oz medium raw scallops: Choose fresh scallops, pat them dry and remove the side muscle for the best texture.
1/4 tsp kosher salt: Enhances the natural sweetness of the scallops perfectly.
30g / 2 tbsp unsalted butter: For sautéing mushrooms and shallots, adding silkiness.
1 eschalot (shallot), finely diced: Gives a subtle, sweet onion flavor that complements the scallops.
200g / 7 oz white mushrooms, diced: Adds earthiness and substance to the béchamel sauce.
2 tbsp plain flour (all-purpose): The base to thicken the creamy mushroom sauce just right.
1/2 cup hot milk (preferably full fat): Creates a smooth, velvety texture in the béchamel.
1/2 cup hot thickened cream (heavy cream): Brings richness and a luscious mouthfeel to the sauce.
1/8 tsp black pepper: A gentle kick of warmth and depth.
1 pinch ground nutmeg: Adds a delicate aromatic note classic to béchamel sauces.
3/4 cup panko breadcrumbs: For that perfectly golden and crunchy topping.
50g / 3 tbsp unsalted butter, melted: Binds the crust ingredients for crispness.
50g / 1/2 cup Gruyère cheese, shredded: Offers nutty, savory flavor that browns beautifully on top.
1/8 tsp kosher salt (for crust): Balanced seasoning ensures every bite sings.

How to Make Cheesy Scallop Gratin with Mushroom Béchamel Recipe

Step 1: Prepare the Oven and Scallops

Start by preheating your oven to 200°C (400°F) or 180°C for fan-forced setups. Meanwhile, gently pat your scallops dry to remove excess moisture. Don’t forget to remove the side muscle—the little chewy “foot”—which can be tough if left on. This little step guarantees tender scallops that melt in your mouth after baking.

Step 2: Cook Mushrooms and Shallots

In a medium-sized pot over medium heat, melt the unsalted butter, then add the finely diced eschalot and diced white mushrooms. Stir them often as they cook for about 4 to 5 minutes until they become soft and fragrant. This forms the flavorful foundation of your mushroom béchamel sauce.

Step 3: Make the Mushroom Béchamel Sauce

Sprinkle in the plain flour and stir constantly for 30 seconds—this cooks out the raw flour taste and starts to thicken the mixture. Gradually pour in the hot milk and cream, whisking quickly until you have a smooth, lump-free sauce. Season with salt, black pepper, and just a pinch of nutmeg for that classic béchamel aroma. Let it bubble gently for about 30 seconds until slightly thickened but still pourable enough to envelop your scallops.

Step 4: Prepare the Cheesy Crust

While your sauce is finishing, mix together the panko breadcrumbs with melted butter, shredded Gruyère cheese, and a pinch of salt. This tasty crust will bake to a gorgeous golden brown, adding a satisfying crunch and nutty flavor that contrasts beautifully with the creamy scallops underneath.

Step 5: Assemble the Gratin

Season your scallops lightly with salt, then divide them evenly among 4 shallow ramekins or gratin dishes. Pour the mushroom béchamel over the scallops, ensuring all gaps are filled to trap that moist creaminess inside. Smooth the surface gently with a spoon or spatula. Finally, scatter the cheesy crust evenly across the top, all the way to the edges for uniform browning.

Step 6: Bake to Perfection

Place the ramekins on a baking tray and bake in the preheated oven for about 20 minutes. The topping should turn a stunning golden color, crisp and irresistible. Once done, let the gratin rest for 2 minutes before serving—this helps everything set beautifully.

How to Serve Cheesy Scallop Gratin with Mushroom Béchamel Recipe

The image shows a close-up of a round white ceramic dish filled with a warm baked casserole topped with a thick, golden-brown crumb crust that looks crunchy and bubbly. The crispy crumbs cover the whole surface with different shades of light brown and darker fried spots. The casserole filling beneath is slightly visible along the sides where it simmers and spills over, showing a creamy, smooth texture in light beige tones. The dish sits on a slightly shiny metal tray with a few browned spots underneath from baking, and another similar dish is blurred in the background. photo taken with an iphone --ar 4:5 --v 7

Garnishes

Sprinkle a little freshly chopped parsley or chives on top just before serving to add a pop of vibrant color and a fresh contrast to the rich dish. A twist of lemon zest or a few drops of fresh lemon juice can also brighten flavors if you want a subtle citrus note.

Side Dishes

This gratin pairs wonderfully with light, simple sides that won’t overpower it. Think crisp green salads with a tangy vinaigrette, roasted or steamed asparagus, or even a delicate rice pilaf. These sides enhance the meal and keep the focus on the creamy scallop gratin.

Creative Ways to Present

Transform your presentation by serving the gratin in small individual scallop shells or mini cast iron skillets for a charming touch. You can also set ramekins on a bed of coarse sea salt to stabilize them and infuse a touch of coastal elegance. It’s a dish that shows off beautifully, so don’t hesitate to get a little fancy!

Make Ahead and Storage

Storing Leftovers

If you happen to have any leftovers from this indulgent Cheesy Scallop Gratin with Mushroom Béchamel Recipe, store them in airtight containers in the refrigerator for up to 2 days. Because of the seafood and dairy content, it’s best eaten fresh but this short storage keeps flavors intact.

Freezing

While this gratin tastes best freshly baked, you can freeze individual portions before baking. Cover ramekins tightly with plastic wrap and foil to prevent freezer burn. They will keep for up to 1 month. When ready to enjoy, thaw overnight in the fridge before baking as directed.

Reheating

To reheat, place the gratin in a preheated oven at 175°C (350°F) for 10–15 minutes until warmed through and the crust regains some crispness. Avoid microwaving if possible as it can make the cheese topping soggy and the scallops rubbery.

FAQs

Can I use frozen scallops for this dish?

Yes, but be sure to thaw them completely and pat dry to remove excess moisture. Fresh scallops yield the best flavor and texture, but frozen can work in a pinch.

What if I can’t find eschalots, can I substitute with onions?

Absolutely, finely diced mild onions can be used. Shallots provide a more delicate, sweeter flavor, but a small amount of onion will still complement the dish well.

Could I make this recipe dairy-free or vegan?

This dish relies heavily on butter, cream, and cheese for its signature taste and texture. While you can try substitutes like vegan butter and plant-based cream, the flavor and texture will differ considerably.

How do I know when the béchamel is the right consistency?

The béchamel should be smooth and pourable but slightly thickened, not too runny and not too stiff. It needs to coat and fill the scallops without sinking to the bottom.

Can I prepare the mushroom béchamel ahead of time?

Yes, you can make the mushroom béchamel sauce a few hours in advance and gently reheat it while stirring before assembling. Just ensure it’s warm and pourable to spread evenly over the scallops.

Final Thoughts

There’s truly nothing like diving into a warm, bubbly dish that celebrates the delicate sweetness of scallops with a rich, creamy mushroom béchamel and a crunchy cheesy topping. The Cheesy Scallop Gratin with Mushroom Béchamel Recipe is a showstopper that feels fancy while remaining incredibly comforting and approachable. Whether you’re cooking for a special occasion or simply treating yourself, I can’t recommend this recipe enough—once you try it, it’s sure to become one of your go-to indulgences.