Peel and julienne the potato into thin strips.
Boil the potato strips in salted water for 2-3 minutes, until just tender. Drain and set aside.
In a small bowl, mix chili oil, soy sauce, black vinegar, sugar, and minced garlic to make the sauce.
Heat a pan over medium heat and toast the Sichuan peppercorns until fragrant. Remove and crush lightly.
In the same pan, add the prepared sauce and potato strips. Toss to coat evenly.
Garnish with green onions and sesame seeds before serving.