Serves 4 as an appetizer
2. In a 1-quart saucepan, cook the cream over low heat, whisking occasionally to prevent it from boiling over, for 8 minutes or until it is reduced by half. Turn the heat to medium and whisk in the butter one piece at a time, stirring constantly, until the sauce is shiny, emulsified, and thick enough to coat the back of a spoon. Add the lemon juice and simmer briefly to blend the flavors.
3. Remove the saucepan from the heat, whisk in the chervil or parsley, salt, and pepper. Set aside in a warm place until ready to serve.
4. Line a serving platter or plates with a layer of rock salt. Set the oysters on the grill cup side down (flat side up). Grill the oysters without turning them for 8 minutes or until they pop open. Use tongs to carefully transfer the oysters to the platter or plates. With the tongs, pry off the top shells. Spoon 1 teaspoon of sauce over each oyster. Adapted from "The Summer Shack Cookbook" Notes: