Wash rice, urad dal, and fenugreek seeds separately. Soak rice and dal+fenugreek in separate bowls with enough water for 4-6 hours.

Drain water and grind rice to a slightly coarse batter. Grind dal to a smooth, fluffy batter. Mix both batters together with salt.

Cover and let batter ferment in a warm place for 8-12 hours or overnight until it doubles in volume and becomes slightly sour.

Heat a cast iron griddle or non-stick pan on medium-high heat. Stir fermented batter gently (don't deflate completely).

Pour a ladle of batter in center and quickly spread outward in circular motion to form a thin crepe. Drizzle oil/ghee around edges.

Cook until edges lift and bottom is golden (1-2 mins). Flip if desired and cook briefly. Fold and serve hot with chutney and sambar.