Wash thoroughly and soak chickpeas in water for a minimum of 8 hours or overnight.
Pressure cook the black chickpeas along with salt and garlic for 10 whistles in medium flame.
Let the pressure release naturally and check for the doneness of the chickpeas. If it's not cooked again cook for about 3 whistles in medium flame.
In a kadai, heat oil and add mustard seeds. Once the mustard seeds crackle, add chana dal and split urad dal.
Once the dals are roasted, add finely chopped onions, red chillies and curry leaves.
Now add a pinch of asafoetida and mix well.
Saute till onions are browned.
Once the onions are browned, add chopped tomatoes. Saute till the tomatoes turn mushy.
Next add chopped brinjals. Saute for a few minutes.
Now add curry powder and salt. You can substitute curry powder with sambar powder or can use a mixture of turmeric powder, red chilli powder and coriander powder.
Mix everything together.
Add everything into the pressure cooker containing the cooked chana. You can add water if needed according to your preferred consistency.
Now add tamarind water or tamarind pulp and mix well.
Close the pressure cooker and cook in medium flame for 1 whistle. Let the pressure release naturally.
Garnish with coriander leaves.
Serve hot !!