Place the chicken wings into a deep pan. Pour over the soy sauce and add water to cover. Sprinkle over the sugar and Chinese five-spice powder.
Bring to the boil, reduce to a simmer and cook for 20 minutes.
Remove the wings from the cooking liquid and allow to cool.
Scatter the flour on a shallow plate, place the beaten egg into a shallow dish and scatter the breadcrumbs over a plate.
Dust the wings first in the flour, then coat with the beaten egg and finally roll in the breadcrumbs until evenly covered.
Heat the vegetable oil in a deep heavy-based saucepan until a breadcrumb sizzles and browns when dropped in it. (CAUTION: hot oil can be dangerous - do not leave unattended.) Add the breaded wings to the hot oil and fry until golden-brown. Remove with a slotted spoon and drain on kitchen paper.
Serve the chicken wings straightaway, with the sweet chilli dipping sauce and prawn crackers alongside.