Potatoes a la Creme au Gratin

Cut some boiled potatoes into slices, about an inch in diameter; prepare the same kind of mixture as directed for cauliflowers au gratin; stick some neatly-cut croutons of fried bread round the bottom of the dish, in the form of a coronet; place a close circular row of the slices of potatoes within this border of croutons; spread a layer of the mixture over them; then repeat the row of potatoes and the mixture until the dish is complete: smooth the top over with some of the sauce; shake some fried bread-crumbs and grated Parmesan cheese over the surface, so as entirely to cover it; put the potatoes in the oven for twenty minutes to be warmed through, and serve.