Wash and soak the Chickpeas overnight.
Drain and add enough water to cover the chickpeas and pressure cook.
I do it for 2 whistles - about 10 minutes. The texture should be soft yet must have the bite to it.
While the chickpeas are cooking, lets make the spice powder. Take a skillet, add 1/4 tsp oil to it and roast the spices given under the "Spice (Hot) powder" section (about 4-5 minutes in medium heat).
Cool it slightly and powder it in a processor until fine. Set aside.
Remove the chickpeas from the cooker. Drain the cooking water. You can use it to make stock, soups, add to rasam/sambar(s), or instead of water while making your chapathi dough.
While its draining, lets preparing the tempering. Use the same skillet that you used to roast the Spiced powder previously. Add 1/2 - 1tbsp oil and when hot, add the mustard seeds. When it starts popping, add the Black gram, red chillies and then curry leaves.
Drop the chickpeas to it and give it a quick toss.
Add some salt and the spice powder (add little by little to check the spice level)