Clean the Brussels sprouts. Soak the boletus in the vegetable stock.
Boil Brussels sprouts in salted water for 5 minutes.
Dice the onion and sauté in the butter until translucent. Add the drained Brussels sprouts and cook with them. Add mushrooms, soaking broth, crème fraîche and sherry (if children eat, this can be replaced with broth) and bring to the boil. Season to taste with pepper, salt and nutmeg.
Roast the pumpkin seeds without fat and pour them over the Brussels sprouts together with the coarsely chopped parsley.