Soaking
Soak raw white rice (Sona Masuri or dosa rice), whole urad dal, chana dal, and toor dal, methi seeds together in water.Separately, soak medium poha in water for about 20 minutes.
Grinding:
Drain the soaked ingredients and transfer them to a blender. Add ½ cup water and grind into a smooth batter. Add more water, if needed, to achieve a medium-thick, pourable consistency.Fermentation:
Add salt to taste, then gently mix the batter well with your hand. Mixing by hand helps incorporate air into the batter, making the dosa softer and lighter.Cover the batter and let it ferment in a warm place for 8-12 hours. In cold climates, use an oven with the light on or the Instant Pot Yogurt mode to help maintain a warm temperature.
Fermentation is done when the batter doubles in volume and develops a slightly sour smell. Add sugar, stir the fermented batter gently. Mix well before making the dosa.
Cooking:
Heat a non-stick dosa tawa and pour a ladleful of batter onto it. Spread the batter in a circular motion to form a thin dosa. Drizzle a little ghee or oil around the edges and on top for extra crispiness.Cook until the bottom turns golden brown, You dont have to cook both sides. Spread a tasty potato masala mixture over the dosa. Serve hot with coconut chutney or sambar.