ESCALLOPED FISH AU GRATIN

Add one egg well-beaten to three cupfuls of seasoned mashed potato. Make a border of the potato around a stoneware platter. Put a layer of Béchamel Sauce on the bottom of the platter, then a layer of cold cooked flaked fish, cover with sauce, sprinkle with crumbs and grated cheese, dot with butter, and brown in the oven. Serve in the same dish.