Soak the split green gram, rice and urad dal in water for 4-5 hours. Then wash it 2-3 times and crush it coarsely into a thick grounded paste without using water.
Pour the paste in a bowl and beat it well using a whisk till it becomes almost double in quantity. Add onion, green chilly, ginger, garlic, coriander, hing, salt, baking soda and mix it together.
Heat some oil on medium-high flame and start frying the dal vada. When the vadas are halfway done take them out and keep them aside.
Just before serving the vadas, refry them until golden brown.
Green Hummus
Add all the ingredients to a blending jar and blend them until it turns into a smooth paste.