Medhu vadai is a popular South Indian snack made from urad dal (split black lentils). It is also known as ulundu vadai or urad dal vada. The lentils are soaked, ground into a batter, and then deep-fried until crispy and golden brown. Medhu vadai is typically served with coconut chutney and sambar as a breakfast item or as a snack. It is crispy on the outside and soft and fluffy on the inside. Some variations of this dish include adding ingredients like onions, green chilies, and curry leaves to enhance the flavor.