Begin by rinsing your waxy potatoes in cold water, scrubbing gently to remove excess starch. Slice into ¼ inch rounds.

In a large pot, bring salted water to a boil. Add sliced potatoes and blanch for 30 seconds to 1 minute. Drain and cool them in ice water.

In a mixing bowl, combine soy sauce, black vinegar, homemade chili oil, minced garlic, green onion, and crushed red chili flakes. Stir well.

In a small pan, heat oil over medium heat. Pour hot oil over the sauce mixture, adding Sichuan peppercorns if using.

Drizzle the sauce generously over cooled potatoes, tossing gently to coat. Sprinkle with sesame seeds and cilantro before serving.