Oven-baked potatoes, tomatoes, and onions
4 medium potatoes
3 medium tomatoes
1-2 medium onions
1 C breadcrumbs
3/4 C freshly grated Parmesan or other sharp cheese
Extra virgin olive oil
Freshly grated pepper
1) Preheat oven to 350°F. Spread olive oil in the bottom of a square dish; the deeper it is, the more layers to the gratin you can add.
2) Slice the onions (1 or 2 depending on taste), potatoes, and tomatoes very thinly. Layer the onions on the bottom of the pan, overlapping them. Then layer the potatoes, overlapping a bit, and the tomatoes, not overlapping. Cover with breadcrumbs and Parmesan cheese, and grate black pepper over top.
3) Repeat layers of onion, potato, tomato, breadcrumbs and cheese until desired height; you may need more or less tomato and potato. End with a topping of breadcrumbs and cheese.
4) Cover the pan with tinfoil and bake in the oven for an hour. The tomatoes should release enough juices so no water or cream need to be added. Check for softness; when cooked, remove the foil and bake until golden on top, another 15 minutes. Let cool 15 minutes before serving. Excellent reheated!