Now you are all set to start assembling your lasagne. Start with a layer of béchamel, Taleggio and Porcini sauce at the bottom of an oven proof dish. Add a layer of cooled pasta sheets, making sure not to overlap them. Now cover them with a layer of béchamel, Taleggio and Porcini sauce and grated Parmigiano Reggiano. Add another layer of pasta and repeat the layers until you run out of pasta.