In a large bowl, mix together the chicken pieces with the coriander root, shallot, garlic, ginger, fish sauce, oyster sauce, soy sauce, corn flour, sesame oil, white pepper powder, sugar and salt. Once combined, pop in the fridge to marinate for two hours.
500 g chicken thighs, 2 tbsp coriander root, 1 shallot, 2 tbsp garlic, 1 tbsp ginger, 1 tbsp fish sauce, 2 tbsp oyster sauce, 2 tbsp soy sauce, 1 tbsp cornstarch / cornflour, 1 tsp sesame oil, 1 tsp white pepper, pinch sugar, pinch salt