Using a small mixing bowl, whisk together the chicken stock, cornstarch, soy sauce and sugar. Set aside.
Using your skillet over medium high heat, add the sesame oil, garlic, ginger and green onions and cook until fragrant, for about 4 to 5 minutes, stirring continuously. Add the hot bean paste, ground Sichuan pepper and spicy bean sauce. Taste and adjust ingredients according to your taste. Continue sautéing for a few more minutes, or until heated through.
Add the tofu and the eggplant and stir together gently so that the tofu and eggplant gets nicely coated with the sauce. Add more spicy bean sauce if needed.
Whisk together the chicken stock mixture again and then pour it over the tofu and eggplant. Toss gently to coat, and let cook until the sauce thickens, for about 5 to 6 minutes. You can turn up the heat a bit if needed.
Serve with white or brown rice and garnish with diced green onions.