Finely chop prawn meat. Add to a bowl along with pork mince, ginger, spring onion, shiitake mushrooms, soy sauce, shaoxing wine, sesame oil, white pepper and corn flour.
Using chopsticks, stir filling in one direction until consistency becomes 'sticky'.
Place a wonton wrapper on your palm. Scoop approximately two tablespoons of filling on to the wrapper.
Move dumpling to rest on the sides of your thumb and pointer finger.
Using the back of a spoon, press the filling down gently, letting the wrapper naturally drop between your fingers. The sides of the dumpling wrapper should fold in. Add more filling if needed. Level filling to the top of the wrapper. Repeat with remaining filling and wrappers. Watch the video for a visual example.
Line a bamboo steamer basket with grease-proof paper. Place dumplings in the basket, with a small amount of diced carrot on top for presentation (if using).
Place basket on top of a pan of simmering water. Steam siu mai for 10-12 minutes until cooked through.
Serve immediately with soy sauce and hot chilli sauce.