Soak both daal in two different containers for 4 to 5 hrs. Take out all water properly. Make a smooth paste and at last mix both paste of urad and moong. Mixing is key point of Dahi vada recipe. Move your hand in one direction, it will take 10min by hand. Don't use hand in all the direction while mixing. Once it is ready to check take small quantity of paste into water. It must float in water. Then mix ginger in very small pieces, green chilli cut in very small pieces and salt to taste.

Dahi vada without Tamarind chutney is not complete. Take Tamarind and soak in water for 1 hr. Boil water in one container take soaked Tamarind in boiled water and leave for 10 min. Take pulp separate to make chutney. Take one pan. Use pulp and then mix jaggery based on taste you like as sweet and sour. Keep stirring jaggery and Tamarind pulp till the thickness you like to use in dahi vada. I prefer little thick chutney for Dahi vada.

Prepare dahi vada masala, Roast cumin seeds, black pepper and red chilli and make smooth powder.

Last step, Mix curd very well and add black salt as per taste. Take water in one container. Boil for 2 min mix hing and little salt based on how did you use while making vada. Take vada from box as many you want to serve now. Soak into hing water for 10 to 15 min. Take out from the water use both the hand to take out all remaining water from vada. Now add mixed Dahi on top and use Tamarind chutney and dahi vada masala. And serve it.