Heat a wok over medium-high heat, and add the oil, garlic, and black beans. Stir-fry for 30 seconds. Then add the tofu strips, and stir-fry for another 2 minutes.
Now add the peppers, Shaoxing wine, light soy sauce, sesame oil, white pepper and sugar. Stir-fry for a few minutes until everything is well combined. Add salt to taste, and serve.