Ravioli with Ricotta and Spinach

1: Wash the spinach well. Place in a saucepan, cover and cook until tender, about 5 minutes. Drain. Cook frozen spinach according to the package instructions. When cool, squeeze out as much moisture as possible. Chop finely. 2: Combine the chopped spinach with the ricotta, egg, Parmesan and nutmeg. Season with salt and pepper. Cover and set aside. 3: To make the pasta, place the flour in the center of a clean, smooth work surface. Make a well in the middle. Break the eggs into the well. Add a pinch of salt. 4: Start beating the eggs with a fork, gradually drawing the flour from the inside walls of the well. As the paste thickens, continue mixing with your hands. 5: Incorporate as much flour as possible until the moisture forms a mass. It will still be lumpy. If it still sticks to your hands, add a little more flour. Set the dough aside. Scrape off the dough from the work surface until it is smooth. 6: Lightly flour the work surface. Knead the dough. Work for about 10 minutes, or until the dough is smooth and elastic. 7: Divide the dough in half. Flour the rolling pin and the work surface. Pat the dough into a disk and begin rolling out into a flat circle. Roll until it is about 1/8 inch thick. Do the same with the second half of the dough. 8: Cut the dough into sheets. Place the small teaspoons of filling along the pasta in rows 2 inches apart. Cover with another sheet of pasta, pressing down gently to expel any air pockets. 9:Use a fluted pastry wheel to cut between the rows to form small squares with filling in the center of each. If the edges do not stick well, moisten with milk or water and press together. 10: Place the ravioli on a lightly floured surface and allow to dry for at least 30 minutes. Turn occasionally so they are completely dry on both sides. Bring a large pan of salted water to a boil. 11: Heat the butter and sage together over very low heat, taking care that the butter melts but does not darken. 12: Drop the ravioli into the boiling water. Stir gently to prevent them from sticking together. They will be cooked in very little time, 4-5 minutes. Drain carefully and arrange in individual serving dishes. Spoon on the sauce and serve at once.