Preheat your pan over medium heat. Add the oil to a pan large enough to hold all the ingredients.
When the oil starts to shimmer add the diced onion. Cook until lightly brown.
Add the garlic ginger paste. Cook until it stops sputtering - about 30 seconds.
Push the onion mixture to one side. You should have a puddle of oil in the pan. If you don't add a splash. You need this to cook the spices.
Turn down the heat to medium low. Add the whole spices, the curry leaf and the fresh green chilies. Cook for around 30 seconds.
Now add in the powdered spices. Stir those into the oil. You want them well coated in oil so they bloom. If it looks like the powdered will stick add a bit more oil. This is important. Cook for around 30-45 seconds.
Toss in the chickpeas and the water or stock and bring to a simmer. Cook, covered, for as long as it takes to get creamy chickpeas and a little body in the sauce. This will vary with the brand of chickpea. Somewhere between 20 and 60 minutes. Keep an eye on the water level. Add more as required. In the end you want your sauce to have a bit of texture so don't drown the chickpeas. You are going for around half the liquid volume you started with. This is the part that's up to you. It's hard to predict how much green chili pickle flavour you will want. Remember you haven't added any salt yet so everything will taste a bit flat. There's salt in pickle and I don't know how much there is in the brand you picked.
Add 2-3 tsps of green chili pickle. Stir and taste. If you think it could use more taste add another tsp. Repeat until you get a flavour profile that works for you. I use 6 tsps for the brand I use (Mother's).
Now taste for salt and adjust accordingly. I used 1/2 tsp but the chickpeas were pretty lightly seasoned. You may not need any more salt.
I love this as a side dish to just about anything or as a vegetarian main course.