The Godwulf Manuscript Ch. 7

Spenser found a recipe in a French cookbook a girlfriend gave him.  It's "a complicated affair with cream and wine and lemon juice and shallots..."  

1 lb or 2 cups sliced scallops
3/4 cup dry white vermouth
2 cups sliced fresh mushrooms
1/2 tsp salt
white pepper
1/2 bay leaf
2 Tb minced shallots 

Place ingredients in pan, add water if needed to almost cover. Bring to a simmer, cover the pan, and simmer very slowly for 5 minutes. Remove scallops and mushrooms with
a slotted spoon; turn heat to high and boil down cooking liquid until reduced to 1 cup. Strain and reserve.

3 Tb butter
4 Tb flour
the 1 cup hot scallop liquid
3/4 cup milk
2 egg yolks
about 1/2 cup heavy cream
salt, white pepper, lemon juice
3 Tb grated Swiss cheese
1 Tb melted butter
6 Scallop shells or a shallow 3 cup baking dish

Melt butter in pan, stir in the flour, and cook slowly for 2 minutes until smooth and bubbly; do not let it brown. Remove from heat and beat in the scallop liquid. Stir with a wire whisk over moderately high heat until sauce thickens; thin out with milk. Blend egg yolks in a bowl with half the cream; beat the hot sauce into the mixture in small driblets (take your time, you don't want the egg to scramble.) Return to pan and stir over moderately high heat until sauce comes to the boil; thin out as necessary with more cream. Carefully correct seasonings, adding lemon juice if needed.

Fold two thirds of the sauce into the scallops and mushrooms, and spoon into lightly buttered shells or baking dish. Spoon on the remaining sauce; sprinkle with cheese and butter. Brown under the broiler for 5 minutes.

Variations:
Toss 3/4 cup soft breadcrumbs with the melted butter and sprinkle over the top with the cheese.
Some recipes call for adding a few Tb of cheddar into the scallop mixture.