1Melt 1 tablespoon butter in a saucepan and saute` the shallots. Cook briefly and then add the mushrooms. Cook until wilted and add salt, pepper and wine.
2Add scallops and bring to a boil. Cook until scallops are heated through, stirring gently as necessary. Take care not to let scallops overcook or they will toughen.
3Using a slotted spoon, remove and set aside the scallops and mushrooms. Reserve liquid (about 3/4 cup).
4Melt 2 tablespoons butter and add flour, stirring rapidly with a wire whisk. When blended add the reserved liquid; stirring until thickened and smooth.
5Add the milk and the 1 cup of cream. Cook for about 5 minutes. Add salt and pepper to taste along with a pinch of cayenne pepper.
6Whip remaining 2 tablespoons cream and fold into the sauce.
7Using scallop shells or ramekins, spoon equal amounts of the scallop/mushroom mix into each shell.
8Spoon sauce over the scallop.
Preheat the broiler to high.
Mix together the bread crumbs, melted butter, and Gruyere cheese; divide and spoon the mixture evenly over each dish of scallops. Place the dishes about 5-6 inches from the broiler and cook until the scallop mixture is hot, bubbly, and browned on top. Sprinkle with lemon juice and serve immediately.