To make this CrockPot LoMein gluten free, replace the angel hair spaghetti with certified gluten-free spaghetti, rice noodles, or gluten-free lo mein-style noodles. Use certified gluten-free soy sauce or tamari, and verify that the oyster sauce, chili paste, ginger paste, sesame oil, brown sugar, pork, vegetables, and water chestnuts are gluten free. Use clean cookware, utensils, and prep surfaces to avoid cross-contact with gluten-containing ingredients.