Cut the chicken wings in two pieces and save the top joint of the chicken for another dish. For this recipe you need just the middle joint and the wing tip. With a small, pointed knife remove bones from mid-joint. Run the knife around the top of each bone, push the flesh down to expose the bone and carefully twist each bone out.
Put mince in a food processor with the fish sauce, spring onions and coriander. Crush garlic to a paste with the sugar and add together with the black pepper and shreds of lime leaf. Process until well mixed.
Fill each chicken wing with mixture but do not overfill or they will burst when steamed. Secure tops with small poultry skewers or cocktail sticks. Place the wings on heatproof plates and steam over boiling water for about 7 minutes. Leave to cool. Roll in rice flour or wheat flour and dust off excess.
Heat oil in a wok and deep-fry the wings until they are golden brown. Drain on paper towels and serve with a dipping sauce or bottled chilli sauce.