01 - Blanch the green beans in boiling water for 2 minutes, then drain and rinse under cold water. Pat dry thoroughly.
02 - Heat 1 tablespoon vegetable oil in a large wok or skillet over high heat. Add green beans and stir-fry for 3 to 4 minutes until blistered and slightly charred. Remove and set aside.
03 - Add remaining 1 tablespoon oil to the wok. Add Szechuan peppercorns and fry for 30 seconds until fragrant, then add garlic, ginger, and scallions. Stir-fry for 1 minute.
04 - Add ground beef and cook, breaking it up, until browned and just cooked through, about 4 to 5 minutes.
05 - Stir in chili bean paste, soy sauce, oyster sauce, Shaoxing wine, sugar, white pepper, and chili flakes. Cook for 1 minute until fragrant.
06 - Return green beans to the wok and toss to combine. Stir-fry for another 1 to 2 minutes until everything is well coated and heated through.
07 - Drizzle with sesame oil, toss, and serve hot.