Ingredients for 8 servings:
1. 4 lbs potatoes, pared and very thinly sliced (8 cups)
2. 2 large onions, thinly sliced (3 cups)
3. 1/2 cup butter
4. 1/2 cup freshly grated parmesan cheese
5. cayenne pepper, to taste
6. salt and pepper

Directions:
1. Preheat oven to 400°F.
2. In a buttered 13×9 inch baking dish, place 1/3 of the potatoes and 1/3 of the onions; sprinkle with salt and pepper and dot with 1/3 of the butter.
3. Do this twice more.
4. Cover and bake for 45 minutes or until tender.
5. Uncover and bake until top is lightly browned.
6. Remove from oven, let cool for 5 minutes.
7. Loosen around edge and invert on a heat-proof platter.
8. Sprinkle cheese and cayenne on top and return to oven to brown cheese.