The key to a soft, fluffy set dosa lies in the rice-to-urad dal ratio, proper fermentation, and cooking on a low to medium heat.
Achieving the perfect soft and fluffy set dosa involves a few crucial steps:
Rice-to-Urad Dal Ratio: Use a higher proportion of rice compared to urad dal. A common ratio is 3:1 or even 4:1 (rice to urad dal). This creates a lighter batter.
Soaking: Soak the rice and urad dal separately for at least 4-6 hours. This allows them to hydrate fully, leading to better grinding and fermentation.
Grinding: Grind the urad dal first until it's light and fluffy. Then, grind the rice to a slightly coarse consistency. Avoid over-grinding, which can make the dosa dense.
Fermentation: This is the most critical step. Ferment the batter in a warm place for 8-12 hours, or until it has doubled in volume. The fermentation process creates air bubbles, resulting in a soft and fluffy dosa. Adding a pinch of sugar or fenugreek seeds can aid fermentation.
Consistency: The batter should be thick but pourable. If it's too thick, add a little water to adjust the consistency.
Cooking: Cook the dosa on a lightly oiled, preheated griddle or tawa over low to medium heat. Cover the dosa while cooking to trap steam, which helps it cook evenly and remain soft. Cook only on one side; set dosas are not flipped.
Avoid adding salt to the batter before fermentation, as it can hinder the process. Add salt just before making the dosas. Also, using a cast iron skillet can help distribute heat evenly, but ensure it's properly seasoned to prevent sticking.