In a saucepan, add coconut oil and 1 cup + 1/2 cup of water and bring to boil. When it is boiling well and you see bubbles, add the rice flour (Have 1/4 cup of water boiled in separate pan/kettle)
For the flour that I used, the extra 1/4 cup hot water was not needed. If you feel the dough is dry, add 1 tablespoon of water, else no need to add. Water added should be boiling hot water, so it's better to keep 1/4 cup hot water separately
Cook till it comes to non sticky dough consistency. Cover the dough with a damp cloth, as it tends to dry soon
When the dough is cool enough to handle, make small spheres (Marble Size). Since rice flour is gluten-free they tend to be sticky, so greasing hand with coconut oil helps
Grease the idli plate and place the kozhukattai and steam them for about 8- 12 minutes. Remove from the plate when it comes to room temperature