Mix the minced prawns, spring onions, sesame oil and soy sauce together in a bowl.
Lay the wonton wrappers on a clean surface and place one tablespoon of the mixture into the centre of each wrapper.
Draw up the sides of each wonton wrapper, leaving the top exposed. Place into a bamboo steamer and cook over a pan of boiling water for 6-8 minutes.
Serve directly from the steamer basket.