Soak basmati rice in water for almost 1 hour.
Put the soaked basmati rice, boiled rice, desiccated coconut, water and sugar in the mixer and grind, till smooth( like dosas consistency).
Pour this in a large bowl and add yeast and mix well.
Leave this for around 4 - 5 hours or till the mixture rises.
Add salt to this mixture and mix well.
Heat a tawa or nonstick vellappa chatty and make yummy vellappams.
:- Serve hot with chicken curry.