Place cooked basmati rice, onion, ginger, curry leaves, turmeric, cumin and coconut milk in a food processor or blender. Blend until the ingredients form a smooth.
Place blended rice mixture in the fridge for a couple of hours or over night if you would prefer.
When ready to make your doughnuts place rice mixture in a bowl and add rice flour and plain flour. Mix to form a slightly wet dough.
Place dough on a well floured surface and kneed for one minute until smooth.
Tear off large walnut size pieces of dough and roll in to a ball. With your finger wiggle a hole into the middle of each ball of dough to form a doughnut. These are meant to be rustic looking doughnuts, embrace their uneven form.
Use a deep fryer or fill a saucepan or wok one third of the way with oil (I use canola). Heat oil to 170°C (340°F), or test with a cube of bread, if it goes golden in 15 seconds the oil is the right temperature.
Cooking around 4 or 5 at a time, carefully drop doughnuts into oil. As they cook they will rise to the to of the oil, they are ready when they are golden brown, this will take around 5-8 minutes. Try one from the first batch to make sure they are cooked through. Repeat with remaining doughnuts.
Serve doughnuts immediately with fresh coconut chutney.