Heat the oven to 400 F.
Flake the crab well.
In a bowl combine the crab, 2 tbsp of the melted butter, nutmeg, salt, pepper, vinegar and crumbs.
Toss lightly with a fork to mix well.
Turn the crab mixture into a buttered baking dish.
Drizzle with remaining butter.
Bake 17.5 minutes until lightly browned on the top.
Serve on toast.