Clean and soak chana dal in some water for 2 hours. Drain the water completely and keep 2 tbsp of soaked dal separately.
Add the remaining portion in your grinder along with red chillies, green chilli, salt to taste, asafoetida and curry leaves and coarsely grind it. Transfer the content in a bowl along with the dal kept seperately and mix it well.
Heat oil in frying pan. When oil starts getting smoky, reduce the flame.
Make small balls of the lentil batter and flatten the ball with your hands and drop it in oil carefully. Fry it on low flame for few minutes.
When it turns golden brown on both sides, drain excess oil, remove from the pan and serve it hot.
Do not over soak the lentil. Drain the water completely before grinding it.