- 1 flank steak (about 2 pounds)
- 1 cup peanut oil
- 1 tablespoon soy sauce, divided
- 1 tablespoon chinkiang vinegar, divided
- 1 tablespoon Shaoxing wine (or dry sherry, if unavailable)
- 2 tablespoons fermented chili bean paste
- 2 teaspoons sugar
- 2 medium carrots, cut into fine julienne
- 2 stalks Chinese celery (or regular celery), cut on a sharp bias into 1/4-inch slices
- 1 medium clove garlic, minced (about 2 teaspoons)
- 12 hot Chinese dry chili peppers, seeded
- 2 teaspoons toasted and ground Sichuan peppercorns
Cut steak with the grain into 2- to 3-inch wide strips. Cut crosswise into 1/4-inch strips. Combine steak and oil in wok and cook over medium-high heat, stirring occasionally. Beef will initially give off lots of moisture and eventually begin sizzling and frying. Beef is done when deep brown, crisp at edges, but still pliant, about 10 minutes. Remove from oil with a slotted spoon, drain on paper towel-lined plate, and transfer to medium bowl. Add 1 teaspoon soy sauce and 1 teaspoon chinkiang vinegar and toss to combine.
Combine remaining soy sauce, vinegar, wine, chili bean paste, and sugar in small bowl and whisk until sugar is dissolved.
Pour out all but 1 tablespoon oil from wok and discard. Heat wok over high heat until smoking. Add carrots and celery and cook, stirring and tossing constantly until lightly charred about 30 seconds. Add garlic and chilis and cook, stirring constantly, until fragrant, about 15 seconds. Add beef and sauce and toss until well-coated, and sauce is slightly cooked down, about 30 seconds. Add half of Sichuan peppercorn and toss to combine. Transfer to platter and sprinkle with remaining Sichuan peppercorn. Serve immediately.