Chef John's Oysters Rockefeller

Preheat an oven to 500 degrees F (260 degrees C). Pour rock salt into a large shallow casserole dish.

Combine watercress butter bread crumbs green onions celery tarragon Italian parsley anise-flavored liqueur salt black pepper and cayenne pepper in a food processor; blend until smooth.

Place 8 to 12 shucked oysters on top of the rock salt. Spoon 1 to 2 teaspoons of watercress mixture a top each oyster.

Bake in the preheated oven until oysters are firm and butter has melted about 5 minutes. Repeat with remaining oysters.