Soak urad dal overnight or for 6-7 hours.
Once soaked, drain the water and wash it with fresh water.
Add the soaked urad dal to a blender.
Now add little water at a time, and blend it to a smooth paste. Blending this dal takes time, we need thick paste here, so adding water little by little we need to make a fine paste.
Urad dal paste (black gram paste) is ready.
Add roughly chopped ginger, cumin seeds, green chillies, and 6-7 curry leaves.
Add salt to taste and hing (asafoetida). For gluten-free vada, skip adding hing.
Mix the batter well and whisk it for a couple of minutes so the batter gets nicely aerated and the vadas become light crispy and fluffy.
Meanwhile, in a kadai heat oil for the vadas to deep fry.
Apply water to your plam and take a ball of this urad batter. Using your thumb make a hole in the centre.
Gently drop the vada into the hot oil. Do not overcrowd.
Fry the medu vada from both sides till they are golden brown in colour. Keep the flame on medium. Fry the remaining vadas in the same manner.
Delicious crispy, fluffy medu vadas are ready. Serve with hot sambar, rasam along with coconut chutney and coffee by the side!