Soak the mushrooms in cold water for 24 hours, then drain and toss them into a marinade of extra virgin olive oil (1 tbsp), salt, pepper, chopped parsley, rosemary and coarsely chopped garlic. Let them rest overnight, then remove the garlic.
Peel and cut the Jerusalen artichoke into chunks, then toss all the ingredients except the courgettes and saffron into a blender and pulse a few times until coarsely blended, occasionally stopping to scrape down the blender jar. Let it rest in the fridge.
Peel the courgettes and cut them into tagliatelle with a potato peeler or a mandolin. Put your tagliatelle into a colander, add some salt and let them drip dry for about 20-30 minutes. After this, wrap them in kitchen paper and squeeze slightly to get rid of as much water as possible. Place the tagliatelle in a bowl, add saffron powder and mix well until their colour is homogeneous. Serve the sauce over tagliatelle with some walnut halves and a sprinkle of parsley.
This recipe was created in cooperation with Stefania from the wonderful food blog La Tortoise.