Add 1 tablespoon vegetable oil to a wok heated over high heat and stir fry shallots and garlic until golden.
Add in mushrooms, soy sauce and sugar and stir fry until fragrant.
Next, add in ground pork, light soy sauce, dark soy sauce, sugar, and black/white pepper and continue to sauté until cooked.
Add in the chicken, light soy sauce, black pepper, dark soy sauce, granulated sugar, Shaoxing wine, tapioca starch and sesame oil. Continue to saute until chicken is almost cooked through.
In a bowl, combine the slurry ingredients: cornstarch, water, oyster sauce and sesame oil.
Pour the slurry into the meat mixture, and cook for another 2 minutes, until thickened.
Transfer the filling mixture into a bowl.