Peel and cut short the stems from a pound of good-sized mushrooms; put them in baking pan, gills up; put a tiny bit of butter in each, sprinkle with salt and pepper. Run them in a hot oven for fifteen minutes; then pour in the pan about a gill of cream and one gill of oyster liquor that has been boiled and strained; bring to boiling point. Dish the mushrooms, cover them over with the oysters, add two tablespoonfuls of sherry to sauce. Make it very hot and pour it over.