Grinding,Frying(Bhoona)and freezing onions makes Indian cooking a breeze. Fried(Bhoona)onions is the base for most curries,Rajma,Chana,Paneer and Meat dishes.
Its important to know that you dont have to peel and grind all of the onions before starting. I start with a few,grind,add to oil,stir,while that is cooking, I work on the second batch of peeling,chopping and grinding and adding to the same pan.The first hour is pretty much just drying the water.