Press the spinach dry with a plate or your hand to remove excess liquid. In a food processor, whip the spinach and one of the eggs until smooth. Make a mound with the flour, plus a pinch of salt. Then make a well in the middle in which to put the eggs. Beat the eggs with a fork and then slowly use the fork to incorporate the flour. Once the eggs are absorbed, use your hands to knead the dough. Mix in the spinach. Knead for 10 minutes until smooth. (You can also use a kitchen mixer with a knead attachment to accomplish the foregoing.) Wrap the dough tightly in plastic and set aside for 20 minutes.
Cut the dough into 4-6 pieces of equal size, but use only one piece at a time (leaving the remaining dough wrapped in plastic). If you are doing this the old fashion way, with a rolling pin, then roll it out, fold it back several times, and continue this process until thin. Alternatively, pass it through a pasta machine until thin (or until it goes through the second thinnest setting at least twice).
Prepare the Filling:
In a large bowl, combine the goat cheese, ricotta, egg, salt and pepper. Mix until smooth.
Prepare the Ravioli:
Place the pasta sheets on a cool dry surface. Using a teaspoon, place spoonfuls of filling evenly spaced on half of the dough, leaving a little space between spoonfuls. If not using a serrated pastry cutter, brush the space around each clump with the beaten egg. Fold over the other half of the dough, and cut the ravioli with a serrated ravioli cutter or pizza cutter into squares. If necessary, press the edges with your fingers or a fork to seal them.
Prepare the Sauce:
In a large skillet, melt the butter. Add the tomatoes, salt, and pepper. Cook over medium heat for about 10 minutes, until slightly wilted.
Bring a large pot of salted water to a boil. Drop in the ravioli and let them cook for 2- 3 minutes.
Drain and place in a serving dish and cover with the tomato mixture. Sprinkle with Parmigiano. Serve immediately.