Preheat the oven to 400° F. Choose a shallow 1-1/2 to 2 quart baking dish that is attractive enough to serve from and rub it with oil. Sprinkle both sides of the eggplant slices with salt (to draw out their moisture) and spread them out in one layer on a platter or board. After 20 minutes pat the eggplant dry with paper towels. Dip each slice in flour and shake off the excess. In a heavy 10" to 12" skillet, heat 1/4 cup of olive oil until a light haze forms over it and brown the eggplant slices a few at a time, working quickly to prevent them from soaking up too much oil. If the oil cooks away, add more. As eggplant browns, transfer the slices to fresh paper towels to drain. Now pour 1/4 inch of the tomato sauce into the oiled baking and serving dish. Spread the drained eggplant slices over the sauce, top them with a layer of mozzarella cheese, and sprinkle over it part of the grated Parmesan cheese. Repeat with 1 or 2 more layers (depending on the capacity of the baking dish), but be sure to finish up with layers of the tomato sauce, mozzarella and Parmesan. Cover the dish snugly with foil and bake in the middle of the oven for 20 minutes. Remove the foil and bake uncovered for 10 minutes longer. Serves 4.
Tomato Sauce (Salsa di Pomodorl)
Using a 2 to 3 quart enameled or stainless-steel sauce pan, heat the olive oil until a light haze forms over it. Add the onions and cook them over moderate heat for 7 to 8 minutes, or until they are soft but not browned. Add the tomatoes, tomato paste, basil, sugar, salt, and a few grindings of pepper. Reduce the heat to very low and simmer, with the pan partially covered, for about 40 minutes. Stir occasionally. Press the sauce through a fine sieve (or a food mill) into a bowl or pan. Taste for seasoning and serve hot. Makes about 1 1/2 cups.