- Wash moong and rice thoroughly. Soak moong and rice together for 4 to 6 hours. Add ginger, green chilies, salt, and cumin seeds. Place this into the grinder and grind it in to smooth paste using water to get a dosa batter-like consistency. Let the batter rest for 15 minutes. To prepare Pesarattu, heat a tawa and pour a ladle full of batter and spread in a circular motion. Spread it as thinly as you can to make it more crispy. Pour oil over edges. Let it cook until it gets brown in color from the bottom.