1 cup urad dal (black matpe beans; see headnote)
2 cups raw basmati rice (see headnote)
1 tablespoon methi seed (fenugreek; see headnote)
1 teaspoon salt
Vegetable or coconut oil (liquefied)
Rinse the urad dal and rice separately in a fine-mesh strainer to clean and remove any excess starch. Place the rice in one bowl and cover with water. Combine the urad dal and methi seed in a separate bowl and cover with water. Soak each for 6 hours.
Drain, reserving the soaking liquid from the dal.
Combine the dal and a little of the reserved soaking liquid in a high-powered blender; puree until very smooth. Transfer to a mixing bowl. Clean out the blender, then add the rice and some of the reserved soaking liquid; puree until no individual grains or pieces are apparent.
Pour the pureed rice into the pureed dal, stirring until well incorporated. The mixture should be the consistency of pancake batter or slightly thinner. Season with the salt. Cover the bowl with a plate or loose-fitting lid. Let the batter sit at room temperature to ferment for about 8 hours. It will increase in volume and should smell slightly sour when ready. (In warm weather, keep the batter away from sunlight; in cool weather, place the batter in an oven or microwave (turned off) to ferment away from drafts.)
Refrigerate the fully fermented batter if you’re not going to make dosas right away. Otherwise, heat a griddle or 12-inch nonstick skillet on medium-high heat. Once the pan is hot, pour 1/3 to 1/2 cup of batter onto the griddle or pan, and very quickly use the bottom of a ladle or bowl to spread it, in one rapid, clockwise motion, into a thin round that’s 6 or 7 inches across. (If the batter seems too thick, add water to the mixture in the bowl in small increments; if it is too thin, flour can be added to thicken it.)
Use a spoon to sprinkle a small amount of oil on the edges of each dosa for crispness and to ease removal from the cooking surface. When the dosa’s underside is a golden brown, gently roll so that one end is a little wider (a slightly loose cone shape), or fold in half. Transfer to a plate. Repeat with the remaining dosa batter.
Source: Adapted from Ananda Poojary, owner of Woodlands in Langley Park.