For your stock, either use a bouillon cube or make a quick stock using leftover chicken, adding an onion, garlic, thyme, a bay leaf, and salt to warm water.
Mince your shallot and put it in a pan with olive oil (2 tsp) on low-medium fire. The shallot should remain translucent and not brown.
After 5 minutes, add the diced butternut, salt, and pepper, stir for another 10 minutes, then add the stock and cover the pan.
Cook for 15 minutes, mix and keep warm.
After rehydrating the mushrooms in some milk, brown them in a pan (medium fire) with olive oil. After 5 minutes, add the cream, salt, and pepper.
Stir for 5 more minutes, mix, and keep warm. In a soup plate, pour 3 ladles of the squash mix and, using a pastry bag, decorate with the mushroom cream.
Sprinkle chopped hazelnuts on top.