Pasta:

Blend the dry mushrooms until a powder is formed and put in a bowl. Weigh the eggs and pour them in the bowl.
Calculate double the weight of the eggs, which will correspond to the total amount of flour: 2/3 of flour and 1/3 of semolina (e.g. if the 3 eggs weigh 150g, you should use 200g flour and 100g semolina). Add some extra flour if the dough is too soft.
Then, add a pinch of salt and a spoon of oil. If necessary, add a bit of water to soften the dough. Put the dough to rest in the refrigerator wrapped in cling film for at least one hour.

Sauce:

Soak the mushrooms in warm water replacing the water a couple of times. Squeeze and chop the mushrooms, setting aside the last soaking water.
Peel the carrots, clean and wash the celery, the onion, the rosemary and the shallot.
Chop everything and soften in a bit of extra virgin olive oil together with garlic. When the vegetables are nice and soft, add the sausages, crumbled by hand or using a ricer, then brown. Meanwhile, warm up 250g of water.
Once the water from the sausages has evaporated, add the white wine, let the alcohol evaporate, then add the tomato paste and purée.
Finally, add the mushrooms and the soaking water, the warm water, a pinch of coarse salt and simmer for 2 hours.
When the sauce is ready, roll out the pasta and cut strips of about 1.5cm width, i.e. Pappardelle. Cook them in salted boiling water for 2-3 minutes.
Dress the Pappardelle with the sauce and a generous helping of Parmigiano Reggiano cheese.