Let's start with the ragù, which takes the longest to cook. Clean and finely chop the vegetables. In a pan, add two tablespoons of oil, heat it, and then let the vegetables soften.

Add the ground meat and brown it, then deglaze with the white wine. Once the wine has completely evaporated, add the tomato puree, salt, and pepper, and optionally some sugar (depending on the acidity of your sauce).

Cover with a lid and let it cook on very low heat for about 4 hours, stirring occasionally. Once cooked, let it cool. The ragù for lasagna should be quite dry, otherwise, it will make the dish too wet and unmanageable.

Move on to the egg pasta: in a bowl, place the required amount of flour in a mound, beat the egg or eggs, and pour them in the center. Start kneading, and if you see that the egg is not enough, add a little water.

When the dough is manageable, transfer it to a work surface and continue kneading until you get a smooth and compact dough. Wrap it in plastic wrap and let it rest for 1 hour in the refrigerator.

Now for the béchamel sauce: in a saucepan, add the flour and butter to create the roux. When the butter has completely melted and you have a sticky paste, let it cook for a few minutes, then add the cold milk.

Mix the roux well into the milk, add the nutmeg and salt, and let it cook on low heat until it thickens, continuing to stir. The béchamel should also be allowed to cool before use, so it thickens and firms up further.

Return to the pasta: take a portion of dough and start rolling it out with a rolling pin or pasta machine. On a work surface, sprinkle a little semolina flour, pass the pasta through the machine with the roller set to the lowest number.

Pass the pasta through the machine multiple times, folding it in two or three parts each time; this helps the pasta become uniform and removes moisture from the dough, making it easier to dry and less sticky when cut.

Once you have a non-sticky and elastic sheet, roll it out to the desired thickness. Lasagna sheets should be about 1 mm thick, but I personally prefer them thicker, so mine will be thicker.

Once rolled to the right thickness, cut it to the size you need, and let the lasagna sheets rest for 10 minutes on a cloth or the work surface.

It's time to assemble the lasagna: in a baking dish, create the first thin layer of béchamel and ragù, so the pasta doesn't stick to the bottom. Proceed with the pasta sheet, then again with béchamel and ragù, making sure to cover the corners well, otherwise, they will dry out during cooking.

Sprinkle with grated Parmesan cheese and continue in the same way with all the layers. The last layer will be just with the sauce and no pasta. Cover the lasagna with aluminum foil and let it rest for 1 hour at room temperature.

After resting, preheat the oven to 375°F (190°C) and place the lasagna inside. Bake for 30 minutes with the foil, then remove it and bake for another 10 minutes.

Once cooked, take it out of the oven and let it rest for 30 minutes. This will help the lasagna set and make it easier to portion. If it is still warm when you cut it, once you have placed the portion on plates, put it back in the oven for 8 minutes at about 175°F (80°C).