We advise you to weigh the doses of each ingredient but we are sure that the dish will be so good that next time the weight of the doses will be based on "feelings".
Prepare a pot with water on the fire and bring it to a boil, then add coarse salt as needed. Meanwhile the tagliatelle are cooking, take the asparagus, wash them well, cut off the heads and keep them aside.
Take a small saucepan and pour water into it, and again, bring it to a boil.
When the water boils, add the asparagus stalks and cook them. Once cooked, lift them with a slotted spoon and cut them into chunks. Once this is done, pour them into the blender glass, add two ladles of the cooking water from the stems (still full of mineral salts), add the robiola and reduce everything to a delicious cream. Obviously, the cream must be fluid and allow you to cream the tagliatelle in a large pan, and if necessary, add a little more cooking water to mix easily.
In the meantime, take the pan where you will stir the tagliatelle, and after cutting the speck into cubes and adding a drizzle of oil, add the asparagus heads to fry both the speck and the heads a little, in way to flavor everything. Add a pinch of salt to the pan and cook everything for a few minutes, this to allow the asparagus not to lose their crunchiness.
Now take the previously made cream of asparagus stems, drain the tagliatelle without throwing away the cooking water, and leave some of the same in the pan where you prepared the speck. Put the tagliatelle and the cream of asparagus back in the pan, over high heat for 60 seconds, stir with a wooden spoon, stirring in the sauce and the pasta until you obtain a homogeneous whole. Turn off the heat and pour the grated Parmesan cheese into the pan and our carefully selected hazelnuts in granella or those toasted. Mix everything well, to obtain the right degree of crunchiness and creaminess. Put everything back on the plate and pour again, as you like, the Nocciolab grains or the toasted hazelnuts for garnish.
All you have to do is serve and enjoy all its goodness.