Rinse the Chana dal and Split green moong dal in water several times until the water runs clear. Soak the dals in enough water for 4 hrs and drain the dals completely.
In a food processor, add the drained and soaked dals, green bell pepper, green chilly, ginger, coriander, curry leaves and coconut, grind it coarsely. Do not add any water while grinding.
Remove the mixture in a bowl and add the chopped dill, hing and salt to taste.
Heat oil in a deep skillet to fry the vada.
While the oil gets hot, take a golf ball size of the mixture and slightly flatten them between your palms. Repeat the same with the rest of the mixture.
To check if the oil is at the right temperature, drop little bit of the batter in the oil. if it instantly comes up, the oil is hot enough to fry.
Drop 3-4 of the patties in oil carefully. Fry on medium heat on both sides until golden brown.
Serve hot vadas with green chutney or ketchup.