Cupped Oysters in Spicy Tarragon Jelly

Oysters - Open the oysters gently from the back. Strain the liquid through a fine-mesh strainer to collect it. Remove the oysters from their shells and place them on a rack. Put the shells in a saucepan and boil them in water, then rinse them under cold water and dry them.

Making the gelatin - Finely chop the shallots, then place them in a saucepan with the red wine vinegar, sugar, ketchup, and tarragon leaves. Reduce until the liquid has evaporated, add the remaining oyster juice, bring to a boil, and add the gelatin sheets, which have been softened in cold water and drained. Cool the mixture over ice and remove only the tarragon leaves.

For the horseradish cream - Place the heavy cream in a mixing bowl set over ice, whip it into whipped cream using a whisk, stir in the horseradish purée, and season with fine salt.

Finishing and presentation - Place the oysters in their shells, pour in the jelly, and let it set in the refrigerator. Once the jelly has set, add the horseradish and tarragon cream.