1. Soak the dal in water for 2 hours. Drain and grind with salt to a fluffy batter, using just a sprinkling of water.
2. Add pepper and optional coconut.
3. Heat oil for deep frying, till it is moderately hot.
4. Take a piece of plastic sheet and grease it lightly with oil.
5. Place about 3 Tbsp of the vadai mixture on it.
6. Flatten to a disc, about 1/2 cm thick.
7. Make a depression in the center with your fore finger.
8. Transfer it carefully into the oil.
9. Shape 3 or 4 more vadas and drop into the oil.
10. Fry on moderate heat till the vadas are cooked and golden brown.
11. Well made medu vadas are soft and spongy with a thin crisp skin.

Makes: About 15 To 18 Vadas