In a medium size bowl, soak urad dal 6~8 hours. In a separate bowl, soak idli rice, raw rice and fenugreek seeds for 6~8 hours.
½ cup Urad dal (Black gram dal), rinsed and drained, ¾ cup Idli Rice (parboiled rice), rinsed and drained, ½ cup Rice, rinsed and drained, ½ teaspoon Fenugreek seeds, As needed Water, for soaking and grinding