Heat Extra-Virgin Olive Oil (2 tablespoon) in a large pan or dutch oven. Cook the Carrot (2), White Onion (1), and Celery (3 stalk) over a low heat until they are soft, roughly 2-5 minutes.
Turn the heat to medium-high and add the 80/20 Lean Ground Beef (500 gram) and 80/20 Lean Ground Pork (500 gram).
When the meat has browned and the liquid it releases has evaporated, add the Water (1 cup) and stir.
When the water has evaporated, add the Tomato Passata (250 gram) and Salt and Pepper (to taste). Stir again to mix the ingredients and let them cook on a low heat for at least an hour, or up to 12 hours. Every hour, stir it and add in a tablespoon of water to keep it moist.
Warm the Whole Milk (1 liter) in a saucepan, but don’t let it boil.
In a separate saucepan, melt the Unsalted Butter (100 gram) over low heat. As soon as it has liquefied, take it off the heat and gradually whisk in the All-Purpose Flour (80 gram), making sure that no lumps form.
Place the pan with the butter and flour mixture back on a low heat and add your warm milk, Salt (to taste), Ground Nutmeg (1 pinch), and Ground Black Pepper (to taste). Stir rapidly with the whisk until it thickens and becomes smooth.
Preheat the oven to 390 degrees F (200 degrees C).
To assemble, pour a fine layer of ragu, then place your Lasagna Noodles (6 sheet) on top of the ragu until you have covered it completely. Don’t allow them to overlap too much, as you don’t want any double layers of pasta. Add a layer of the bechamel sauce then grate Parmigiano-Reggiano (to taste) over the top.
Repeat the process in the same order as above until you reach 6 layers of pasta. On the very last layer of pasta, place a slightly thicker layer of bechamel and ragù, as it is the layer most exposed to the hot air of the oven and tends to dry up. Generously sprinkle some more Parmigiano Reggiano on top.
Bake for about 25 minutes. You will know the lasagna is ready when you can see a golden crust around the outside edges on the top layer.
Rest the lasagna for 5-10 minutes before cutting and serving.
Garnish with Fresh Basil (to taste). Serve and enjoy!