Ube Glutinous Rice Donut

For the Ube
115 g ube powder
400 ml coconut cream or coconut milk
1 cup sugar
1 tsp ube flavouring
2-3 drops purple gel food colouring
1 can evaporated milk

For the Glutinous rice dough
2 cup glutinous rice
1/2 tsp baking soda
1/2 tsp salt
2 tbsp sugar
2 tbsp plain flour
14 tbsp hot water
2 tbsp butter