Alchemy is at play here with the delightful union of miso and sherry vinegar, both working to amplify mushroom’s savory, umami notes, and create a rich, layered pasta in just over 30 minutes. Sautéed leeks and mushrooms form the core flavors of the pasta, but it is the addition of miso that completes the dish: Whisked with the starchy pasta water and grated Parmesan, it forms a quick sauce to coat the noodles. A farro, spelt or whole-wheat pasta would nicely complement the earthy flavors of…