In a pressure cooker take ½ cup soaked kala chana, salt, water and 1 medium-sized potato. Pressure cook for 5-6 whistle or until chana is cooked well.
Drain off the water and keep it aside.
In a pan, add oil, a pinch of hing, cumin seeds and green chilli slits. Sauté for a minute.
Now in a bowl, add water, red chilli powder, coriander powder, cumin powder, garam masala, amchur powder, and black salt. Mix well and add masala paste into the oil.
Sauté masala paste on low flame till it separates oil.
Then add boiled chana and cook till masala absorbs into chana.
Transfer the spiced kala chana to a bowl. cool down completely.
Add chopped onion, tomatoes, potatoes, green chilli, mint leaves, masala sing, green chutney, tamarind chutney and coriander leaves. mix well.
Chatpati chana chaat is ready to serve.