Wash the 3 cups of rice properly and soak in water for 3 hours or over night

Wash the soaked rice again then add water and blend till it forms a smooth paste(you can add more water if it's too thick it should be shouldn't be very watery either)

Boil water in a pan and add it to a cup out of the blended rice(like custard) make sure it become thick and also smooth

Pour the custard like paste into the remaining and whisk till it becomes well incorporated and smooth

Add the yeast and mix properly and let it rise for an hour or two in a warm place

Add the sugar,baking powder yeast and salt and mix well

Use a pastry brush and glaze the pan with oil,if you're using a non stick pan,if not make sure the pan gets enough oil(not to much just any amount that'll prevent it from sticking)

Use any measuring cup you want depending on the size you want to pour the batter