Soak the daal for at least 2 hours.
Drain the water completely.
Grind it with just 2-3 tablespoons of water in a Blender or Food Processor.
Beat the batter vigorously for about 5 minutes. It should be light & fluffy.
Add the Baking Soda. Mix well.
Take a tiny blob of the batter & drop it in a small bowl of water to test. If the batter sinks, beat more. If it floats immediately, you are good to go.
Heat enough oil in a large wok for deep frying.
Keep a medium bowl of water on the side.
Wet your hand lightly.
Take a lemon size blob of the batter.
Slide it gently into the hot oil. Fry over medium heat until golden. Repeat.
Soak the fried Vadas in hot water with salt & Heeng. Cover & set aside for 15 minutes.
After 15 minutes, squeeze the Vadas one by one gently & place them in a Serving Dish.
Add Sugar to the Yogurt & whisk well.
Pour it on top of the Vadas.
Sprinkle the Chaat Masala, Jeera Powder & Red Chili Powder.
Top with Tamarind-Date Chutney & Mint-Coriander Chutney.
Chill in the refrigerator.
Enjoy!