Spinach Lasagna with Bolognese Ragu

Mound the flour on a large wooden board or other work surface. With your fingers, make a round well in the center of the flour. Break the eggs into the well. Stir the eggs thoroughly with a fork, then gradually draw the flour, starting with the inside walls of the well, into the eggs, mixing it with the fork, until a soft paste begins to form.

With a dough scraper, push all the remaining flour to one side of the board. Scrape off and discard the bits and pieces of dough attached to the board. Add some of the flour you have pushed aside to the dough and begin kneading gently. As you keep incorporating more flour, the dough will become firmer and your kneading will need to become more energetic. Do not add too much flour, though; you may not need it all.

The moment you have a soft, manageable dough, clean the board again and wash your hands. Flour the work surface lightly and begin to knead the dough, pushing it away from you with the palms of your hands and then folding half of the dough back over itself. As you knead, keep turning the dough: push, fold, over, and turn. Knead the dough for 8 to 10 minutes, adding a bit more flour if it sticks to the board and your hands.

Press one finger into the center of the dough. It is comes out barely moist, the dough is ready to be rolled out. If the dough is quite sticky, knead it a bit longer, adding more flour. When it is ready, the dough will be compact, pliable, smooth and moist.

If you are going to roll out the dough with a pasta machine, it can be used immediately. If you are going to roll it out with a rolling pin, wrap it first in plastic wrap, and set it aside to rest for about 30 minutes. After that time, the gluten in the dough will have relaxed and it will be easier to roll it out. If the dough is too soft and limp when you remove the plastic wrap, knead it for a minute or so to a firmer consistency.

Rolling out the Dough with a Hand-Cranked Pasta Machine

Adjust the rollers to the next setting and run the dough through once; do not fold the dough again. Adjust the rollers to the next setting and run the pasta sheet through the rollers once; continue to adjust the rollers and roll the pasta through the machine until it reaches the desired thinness.

Cut thin wide sheets of dough to fit your lasagne pan.

Place a bowl of cold water on a counter near the stove and spread out some kitchen towels near the bowl. Bring a large pot of water, preferably one with a pasta insert, to a boil. Add the coarse salt and 3 to 4 sheets of pasta. After the water comes back to a boil, cook the pasta for no longer than 20 to 25 seconds. Lift out the sheets with the pasta insert or a large skimmer, trying not to tear them, and plunge them into the bowl of cold water to cool. Immediately remove the pasta sheets, lay them out on the towels, and pat dry with another towel. Repeat with the remaining pasta.

Heat the milk in a small saucepan over low heat.

Meanwhile, melt the butter in a small saucepan over medium-low heat. When the butter begins to foam, beat in the flour with a wooden spoon or a whisk and cook, stirring for about 2 minutes, making sure not to let the flour brown.

Remove the saucepan from the heat and add the hot milk all at once, whisking energetically to prevent lumps. Put the saucepan back over low heat, add the salt, and cook, stirring constantly, until the sauce is medium-thick, about 5 minutes. If the béchamel is too thick, stir in a bit more milk; if it is too thin, cook a bit longer.

Heat the oil and 1 tablespoon of the butter together in a medium saucepan over medium heat. As soon as the butter begins to foam, add the minced vegetables and pancetta. Cook, stirring occasionally, until the vegetables and pancetta have a nice golden color, about 5 minutes. Add the ground beef and pork, raise the heat to high, and cook, stirring and breaking up the meat with a wooden spoon, until the meat and vegetables have a rich brown color and the bottom of the pan is glazed, 7 to 8 minutes.

Add the wine and cook, stirring until most all of it has evaporated. Stir in the diluted tomato paste and season with salt and pepper. As soon as the liquid comes to a boil, reduce the heat to low, partially cover the pan, and simmer for about 2 hours, stirring and checking the sauce every 20 minutes or so. The sauce should be thick, with an appealing nutty brown color, and just slightly liquid. Add a bit more broth or water if the sauce looks to dry.

Add the milk, partially cover, and simmer for 10 to 15 minutes longer. Taste and adjust the seasoning, turn off the heat.

Preheat the oven to 400 F. Generously butter the bottom and sides of a lasagne pan.

Add the béchamel sauce to the ragu and mix well to combine. Cover the bottom of the lasagna pan with a layer of pasta sheets, trimming the pasta to fit the pan if necessary. Spread a thin layer of ragu over the pasta and sprinkle with Parmigiano-Reggiano. Repeat the process one layer of pasta, one layer of ragu and a sprinkle of Parmigiano. Dot the top with the butter.

Place the lasagne pan on the middle rack of the oven and bake until the top pf the lasagne is lightly golden, 15 to 20 minutes. Remove from the oven and let settle for a few minutes before serving.