Place the sweet potato vermicelli in a container and soak in warm water for 1 hour until it is completely soft.
Cut cabbage into shreds.
Put the soaked sweet potato vermicelli in a large bowl. Add 1 tablespoon oil, 1 tablespoon soy sauce and mix well.
Add oil to the pan and heat it, add peppercorns, fry over low heat until slightly charred, remove and throw the peppercorns.
Pour chopped green onion, minced ginger, garlic slices and dried chili peppers until fragrant.
Pour the shredded cabbage and stir-fry over high heat.
Add the vermicelli, add salt, pour a few drops of rice vinegar, stir-fry quickly for 1-2 minutes on high heat.