Prepare the sauce: Combine all sauce ingredients (peanut butter, chili oil, soy sauce, dark soy sauce, Chinese black vinegar, Sichuan peppercorn, sugar, minced garlic, and a splash of noodle water) in a plate or bowl (this will be the final serving dish). If the noodles finish cooking before the pork is ready, add the noodles to the prepared sauce and stir to coat.