Preparation For the dough:Place the flour in a mound on a worktable. Make a well in the middle of the flour and crack the eggs into the well. Mix the flour and egg together with the fork and also work in the butter. Work the dough with your hands until all ingredients are smooth. Wrap the dough and store for an hour. Use a pasta machine to work the dough through the thinnest setting and make pasta sheets. For the filling:Season the eggplant and onion slices lightly with salt and pepper. Coat the slices with oil and grill on both sides until the eggplant and onions are tender. Use a food processor to roughly chop the onions and eggplant. Then mix in the ricotta and grated reggiano cheese and combine with the eggplant and onions. You can use a pastry bag or teaspoon to portion out some of the mixture into the center of the pasta sheets. For the sauce:Heat up the olive oil in a sauté pan. Sauté the shallots until they begin to turn transparent. Toss in the Swiss chard and tomatoes. Allow the Swiss chard to soften a bit then toss in the cooked ravioli. Season with salt and pepper. Toss with some more olive oil and reggiano if desired.