Mix rice flour, urad dal powder, salt, milk and til. Add butter and knead into a soft non-sticky dough, adding water as necessary. Heat oil. Place a small quantity of dough in a chakli mould and press through. While pressing, move the mould in a circular manner to guide the dropping flow of the dough from its bottom to fall gently into the hot oil in the form of a spiral in three to four circles. Deep fry in batches till brown and crisp. Remove, drain and store in airtight jars. Serve, if desired, with pieces of fresh coconut. NOTES : Makes 30