I love the simplicity of this dish. The original dish uses chicken but I find pork fillet a great substitute.
In a mixing bowl, marinate pork fillet slices in the flour and water for at least 20 minutes.
Place 2 tbsp oil and chillies in a wok then turn on heat to low. Cook for 2 minutes or until chillies darken in colour. Drain and remove chillies, reserving the oil.
Using the same oil, turn heat to high and fry the pork slices in batches until golden brown (approximately 3-5 minutes). Use extra oil if required. Return all the pork into the wok then add ginger and onion. Cook for 3 minutes.
Add remaining ingredients (except Szechuan pepper) and stir-fry for another 3 minutes. Turn off heat, sprinkle with Szechuan pepper and serve.