Steamed water chestnut cake

Recipe : ( from Steamed cake & Kuih Muih )
Ingredients :
* A :
- 30g wheat starch
- 30g tapioca flour
- 100g water chestnut powder
- 200g caster sugar
- 250ml thick coconut milk
- 150ml water
* B :
- 8 water chestnuts , peeled , chopped
Method :
Mix all A , cook in a pot over boiling water and stirring until thicken , add in chopped water chestnuts , stir well . Spoon the mixture into greased steaming tin , level the surface and steam in the preheated steamer at high heat for 20 mins . Remove the tin from heat , leave to cool , cut and serve .