Lasagna alla Bolognese

INGREDIENTS :
FOR BOLOGNESE SAUCE :
Extra virgin olive oil 1 tablespoon
50gr carrot
50gr celery
50gr onion
250gr tomato sauce
500gr of minced meat
FOR BÉCHAMEL SAUCE:
1lt of milk
80gr of butter
120gr of flour 0
Salt
Nutmeg

PREPARATION
Begin by finely chopping the knife celery, carrot, peeled and trimmed and onion so as to obtain 50 g for each ingredient.
Heat the oil in a pan and add the chopped vegetables, stewed for about ten minutes on a low heat while stirring, occasionally. After the time the sautéed must be wilted and the bottom of the pan dry. Add the coarse minced beef.
Also the meat will have to brown slowly for about ten minutes, so stir to seal well. Initially will spill all juices but once dried you can blend with 250 g of white wine. As soon as the alcohol has evaporated completely and the bottom is dry, pour the tomato sauce, then add 2 glasses of water.
Add a pinch of salt, stir and cook over medium-low heat for an hour.
At the end of cooking the result must be dense (not too dry for this type of baking preparation). Season to taste with salt and pepper, turn off the heat, stir and set aside the sauce.
Now take care of the preparation of the béchamel sauce: take a small pan and heat the milk. In the meantime, melt the butter in small pieces over low heat in another pan and, when it is dissolved, remove from the heat and add the sifted flour. Stir vigorously with the whip to obtain a mixture without lumps. Then put the pan on the fire, to brown slightly.
When the milk is hot, flavored with grated nutmeg and a pinch of salt. At this point you can add it to the mixture of butter and flour. Stir vigorously the ingredients with a hand whisk and let thicken over low heat: the mixture must be homogeneous and without lumps. Cook the béchamel sauce for about 5-6 minutes on a low heat, until creamy.
Then switch to the composition of the lasagne: take a baking sheet or a rectangular baking dish with dimensions of 30×20 cm.
Spread a line of béchamel and sauce of ragù on the pan evenly over the entire surface, then lay the lasagna and pour again a thin layer of béchamel sauce and one of ragù, mozzarella and the grated Parmesan taking care to cover the entire surface of the pan. Then create another layer of lasagna, (if you prefer also arranged in the opposite direction compared to the first layer so that they are crossed). Then proceed to create a new layer of béchamel sauce. Take care to distribute it over the entire surface of the pan. Add also the meat sauce and continue for all the layers alternating sheets, béchamel sauce, meat sauce, mozzarella and Parmesan cheese.
Finish with a layer of meat sauce and a sprinkling of plenty of grated Parmesan (25-26). Once the baking pan is finished, bake in a static oven preheated to 200 º C. for about 25 minutes (or in a ventilated oven at 180 º C. for 15 minutes): the lasagna will be ready when you see a slight golden crust on the surface. Bake them and let them cool before serving and ENJOY YOUR LASAGNA ALLA BOLOGNESE!!