Heat oil or ghee in a large saucepan over medium-high heat until shimmering. Add cumin seeds. They will sputter and spit for a few seconds. As soon as they are aromatic (about 15 seconds), add the onion.
Cook, stirring frequently, until onions start to leave a brown coating on the bottom of the pan, 3 to 4 minutes.
Add garlic/ginger/chilli paste all at once and stir to combine. Add coriander, turmeric, and 1 teaspoon garam masala. Stir until fragrant, about 30 seconds. Add tomatoes and crush them using a whisk. Add drained, rinsed chickpeas. Add 1/2 cup water.
Bring to a simmer, cover with lid slightly cracked, and reduce heat to maintain a gentle bubbling. Cook, stirring occasionally, until liquid has reduced into a thick stew and spices have melded about 30 minutes.
Stir in remaining garam masala. Season to taste with salt. sprinkling with green chilli on the top. ENJOY!!!