1-First step: get the oven and ramekins ready Preheat the oven to 200°C (400°F) or 180°C fan-forced (350°F). Have four shallow flat ramekins ready, ideally about 11cm in diameter and 2.5cm deep. If you have scallop shells, you can use those too, but place them on a foil-lined tray or a small foil ring for support. Set a baking tray aside so you can move everything into the oven safely and without spills.

2-Second step: prep the scallops Pat the scallops dry with paper towels. This matters because excess moisture can thin the sauce and weaken the crust. Remove the side muscle if you see it, then slice medium scallops in half. Season them with 1/4 teaspoon salt, then divide them evenly among the four ramekins. Spread them out in a single layer so each serving bakes evenly.

3-Third step: make the cheesy crust In a bowl, mix 3/4 cup panko breadcrumbs, 50g melted unsalted butter, and 50g shredded Gruyère cheese. Stir until the crumbs are evenly coated. Set the mixture aside while you make the sauce. Panko is the best choice if you want a crisp, light finish, but regular breadcrumbs will still work in a pinch.

4-Fourth step: cook the mushroom béchamel sauce Melt 30g butter in a pot over medium heat. Add the finely diced eschalot and the diced white mushrooms. Cook for 4 to 5 minutes, stirring often, until the mushrooms soften and the shallot smells sweet. Sprinkle in 2 tablespoons flour and stir for about 30 seconds to remove the raw flour taste. Then slowly pour in 1/2 cup hot milk and 1/2 cup hot thickened cream, stirring as you go so the sauce stays smooth. Season the sauce with 1/4 teaspoon salt, 1/8 teaspoon black pepper, and a pinch of ground nutmeg. Simmer for about 30 seconds until the sauce looks bubbly and pourable, then take it off the heat. You want it thick enough to coat the scallops, but still loose enough to settle into the ramekins. If it gets too thick, add a tiny splash of milk.

5-Fifth step: assemble the scallop gratin Spoon the sauce evenly over the scallops, making sure it fills the gaps in each ramekin. Smooth the top gently so the scallops are mostly covered. Then spread the breadcrumb and cheese mixture all the way to the edges. This helps the topping brown evenly and gives you that classic golden crust people expect from st jacques scallops.

6-Sixth step: bake until golden Place the ramekins on the baking tray and bake for about 20 minutes. The top should look golden and crisp, and the filling should be bubbling around the edges. If your oven runs a little cool, give it another minute or two, but do not overbake. Scallops turn tough if they cook too long.

7-Final step: rest and serve Let the ramekins rest for 2 minutes before serving. That short rest helps the sauce settle and keeps the dish from burning your mouth right away. Serve warm as a starter for holiday dinners or special occasions. If you want a fuller meal, pair it with a simple salad, crusty bread, or a side dish like baked ziti for a comforting dinner spread when you are building a larger family menu.