RAVIOLI STUFFED WITH RICOTTA AND SPINACH

Steps:

• Spoon the ricotta into a large fine-mesh sieve or a colander lined with a double thickness of cheesecloth or a basket-type coffee filter. Set the sieve over a bowl and cover the ricotta well with plastic wrap. Let the ricotta drain in the refrigerator at least overnight or up to 24 hours. Discard the liquid in the bottom of the bowl.
• In a wide braising pan or deep skillet, heat the oil over medium-low heat. Add the leeks and scallions and cook until softened, about 3 minutes. Stir in the chopped spinach and increase the heat to medium. Season lightly with salt and pepper and cook over moderate heat until the vegetables are tender and the liquid is evaporated, about 10 minutes. Set in a strainer and cool completely.
• Stir the fresh ricotta, Parmigiano-Reggiano, parsley, and sautéed greens together in a bowl. Season to taste with salt and pepper and stir in the egg. Chill thoroughly.
• While the filling is chilling, make the pasta dough and let rest.
• Form and cut the ravioli according to directions on page 190. The ravioli should be cooked immediately or refrigerated up to 4 hours. (The ravioli may also be frozen: Place the sheets of ravioli onto a freezer shelf and freeze until solid to the touch. Carefully transfer the ravioli to resealable plastic bags or airtight plastic containers.)
• Bring 6 quarts of salted water to a boil in an 8-quart pot over high heat. Slip the ravioli into the water a few at a time, stirring gently as you do. Cook until the edges of the pasta are tender but still firm to the bite and they rise to the surface, about 6 minutes after the water returns to a boil.
• While the ravioli are cooking, divide the tomato sauce, olive oil, and basil between two large skillets and bring to a simmer over medium heat. Fish out the ravioli with a wire skimmer or large flat slotted spoon, drain them well over the pasta pot, and slide them into the pans of sauce, dividing them evenly. Simmer, stirring gently with a spoon until the sauce is lightly reduced and the ravioli are coated. Remove the pans from the heat, check the seasoning, and add salt and pepper if necessary. Spoon the ravioli into warm bowls or onto a warm platter, sprinkle with the grated cheese, and serve immediately.
• Variation: Butter-Sage Sauce (Conditi all Burro e Salvia)
• Melt one stick (8 tablespoons) unsalted butter in a large skillet over low heat. (The heat should be low enough to melt the butter slowly, without its separating or turning clear.) Add eight to ten whole sage leaves and remove the skillet from the heat. Ladle out about 1 cup of the ravioli-cooking water before you drain them. Either fish the ravioli out of the pot with a large wire skimmer or drain them gently. Add the ravioli to the skillet. Pour in enough of the cooking liquid to make a sufficient amount of creamy sauce to coat the ravioli generously. Bring to a quick boil, then remove from the heat. Stir in grated Parmigiano-Reggiano cheese, salt, and freshly ground black pepper to taste. Serve immediately.