- 2 teaspoons Champagne vinegar
- 1 1/2 teaspoons finely chopped shallot
- Pinch of coarsely ground black pepper
- Pinch of sugar
- 1 teaspoon finely chopped fresh flat-leaf parsley
- 1 1/2 cups kosher or other coarse salt
- 1/2 dozen small oysters, such as Kumamoto or Prince Edward Island, shells scrubbed well and oysters left on the half shell, their liquor reserved and oysters picked over for shell fragments
- 1/2 tablespoon unsalted butter, cut into 6 pieces
- 1 small cluster Champagne table grapes or 2 finely diced seedless red grapes
- Stir together vinegar, shallot, pepper, and sugar and let stand 30 minutes.
- Preheat broiler.
- Spread 3/4 cup salt in an 8- to 10-inch flameproof shallow baking dish or pan. Arrange oysters on their shells in salt, then top each with a piece of butter.
- Broil 4 to 6 inches from heat until butter is melted and sizzling and edges of oysters are beginning to curl, 1 to 2 minutes.
- Stir parsley into mignonnette. Divide remaining 3/4 cup salt between 2 plates and arrange 3 oysters on each. Spoon 1/4 teaspoon mignonnette over each oyster and sprinkle oysters with grapes. Serve warm.