Whisk together the chili oil, chili bean paste and rice vinegar in a small bowl.
Heat a wok over high heat until smoking and pour in the vegetable oil. Add the peppercorns and garlic and toss briefly, and then add the celery and stir-fry until softened, 1 minute. Stir in the tofu and carefully toss until heated through, about 1 minute. Pour in the chili oil sauce and toss well until warm throughout.
Stir in the soy sauce and season with sea salt, black pepper and the lemon juice, adding more to taste.
Transfer to a platter and sprinkle the cilantro and peanuts over the top. Drizzle more chili oil over the salad and serve immediately.