Heat a large pot over medium heat. Once hot, add oil and diced onions. cook for few minutes or until translucent.
Add ginger and garlic paste and saute for few minutes.
Now add red chili powder, turmeric powder, coriander powder, cumin, salt, nigella seeds, chili flakes and amchur powder and cook for 5-6 minutes. avoid burning the spices, add some water if the spices are sticking to the pan.
Add tomato puree and cook for few more minutes .
Add drained canned chickpeas and mix everything together.
Now add half to one glass of water depending on the thickness of the gravy, cover and cook for 5 minutes.Remove from heat.
Garnish with cilantro and green chilies. serve with naan bread or rice.