Having boiled the crabs, extract all the meat from the shell, cut it fine, and season it to your taste with nutmeg, salt, and cayenne pepper. Add a bit of butter, some grated bread crumbs, and sufficient vinegar to moisten it. Fill the back-shells of the crab with the mixture; set it before the fire, and brown it by holding a red-hot shovel or a salamander a little above it.
Cover a large dish with small slices of dry toast with the crust cut off. Lay on each slice a shell filled with the crab. The shell of one crab will contain the meat of two.