Microwave the pizza dough on 50 percent power to soften, 1 to 2 minutes, then let rest 5 minutes. Grease a large plate with vegetable oil; shape the dough into a 9-inch round and place on the plate. Sprinkle with 1 tablespoon sesame seeds and 1/4 teaspoon salt.
Toss the coleslaw mix, vinegar, chili oil, and salt to taste in a bowl. In another bowl, toss the roast beef, sesame oil, scallions and ginger.
Heat 3 tablespoons vegetable oil in a large nonstick skillet over medium-high heat. Add the dough seed-side down and sprinkle with the remaining 1 tablespoon sesame seeds. Cover and fry, shaking the pan occasionally, until the dough is golden, about 3 minutes per side, turning with tongs. Transfer to paper towels, season with salt and cool.
Wipe out the skillet and place over high heat. Add the roast beef mixture and stir-fry until crisp, 1 to 2 minutes. Slice the flatbread in half horizontally. Layer the beef, coleslaw mixture and cilantro on the bottom half. Cover with the top and cut into 4 wedges.
Bing is a Chinese flatbread, often used to sandwich meat, eggs or fried dough for breakfast.
Per serving: Calories 561; Fat 27 g (Saturated 5 g); Cholesterol 27 mg; Sodium 906 mg; Carbohydrate 62 g; Fiber 4 g; Protein 22 g