Made with ground rice, dosas are the Indian version of the crepe.
Soak rice, urad dal, and fenugreek in water to cover for 3 hours. Rinse under running water and drain. Transfer to a food processor fitted with the steel blade, and grind to a smooth yet thick batter. Set batter aside, and let ferment overnight at room temperature.
Add salt and a little water, if necessary, to thin batter. Heat griddle to 350 degrees. Sprinkle hot griddle with water and a teaspoon of oil. Wipe clean with a cloth. Drizzle a little oil on the griddle. Spread evenly over the surface of the griddle, removing any excess with a bench scraper. Using a 1-cup measuring cup or ladle, measure 3/4 cup batter, and pour onto grill. Spread batter out into a 16-inch oval using the bottom of the measuring cup. Using a scraper, remove any excess batter from the top of the dosa. Cook until the surface bubbles and the bottom is golden brown (1 to 1 1/2 minutes). Place filling crosswise in center of dosa. Fold dosa in thirds to enclose filling.