Oysters Rockefeller

Ingredients

• 24 Gulf oysters, large and plump, on the half shell, shucked immediately before assembly; liquor retained in the shell
• 1–2 kg rock salt, spread on baking sheets to bed the shells level and retain heat
• For the sauce
• 115 g unsalted butter, softened
• 30 g flat-leaf parsley, leaves only, finely chopped
• 30 g celery leaf, finely chopped
• 30 g green onion (scallion), white and green parts, finely chopped
• 15 g watercress, leaves only, finely chopped
• 24 tsp Herbsaint or Pernod, 1 tsp per oyster; Herbsaint is the traditional New Orleans choice
• 1 tsp fine sea salt
• 0.5 tsp white pepper, freshly ground
• For the breadcrumb topping
• 60 g fine dried breadcrumbs, a thin layer over each oyster; should brown without burning
• To serve
• 4 lemon wedges
• 1 loaf French bread, sliced, for sopping sauce from the rock salt

Method

1. 1
   Make the sauce. Work the softened butter with the chopped parsley, celery leaf, green onion, and watercress until the mixture is a uniform vivid green paste. Season with salt and white pepper. Refrigerate until needed — up to two days ahead. The sauce is ready when the colour is deeply green and the herbs are evenly incorporated throughout the butter.
2. 2
   Set the oven to 230 °C (or heat the grill/broiler to its highest setting). Spread rock salt to a depth of roughly 2 cm across one or two heavy baking sheets. The salt bed is functional: it holds the shells level so that neither sauce nor oyster liquor spills, and it retains enough heat to keep the oysters hot from oven to table.
3. 3
   Shuck the oysters immediately before assembly — not before. An oyster that sits open for twenty minutes loses liquor, dries at the edges, and tastes flat. Nestle each half shell into the rock salt so it sits without tilting. The liquor pooled in each shell is a flavour component; preserve it.
4. 4
   Place approximately 1 teaspoon of Herbsaint (or Pernod) directly into each shell over the oyster. Spoon roughly 1 tablespoon of the cold herb-butter sauce over each oyster — enough to coat the surface without drowning the oyster or burying its brine. Dust a thin, even layer of fine dried breadcrumbs over the sauce on each shell.
5. 5
   This is where the dish lives or dies. Slide the trays into the oven or under the grill and bake or broil for 4 to 6 minutes at maximum heat. Watch continuously. The dish is done when the breadcrumbs have turned golden, the sauce is visibly bubbling around the edges of each shell, and the very rim of each oyster has just begun to curl. The centre of the oyster must remain soft, plump, and translucent. An oyster that has shrunk to half its raw size is overcooked — rubbery, stripped of brine, and the dish is lost. Remove the trays the moment the edges curl.
6. 6
   Transfer the shells on their rock salt beds directly to the table without delay. Serve with lemon wedges for squeezing and French bread for sopping any sauce that has pooled into the salt. The dish is ready when each guest can smell the anise rising from the shells before they lift a fork.