Start by making the keema. In a pressure cooker, heat ghee or oil and add all the whole spices. Saute for a minute and add onions, green chili and ginger garlic paste. Once the onions are translucent, add tomatoes and tomato puree. Cook this for 10-15 minutes till the tomatoes look like they are melting and can squashed easily into a pulp. Add keema and the rest of the ingredients along with 1/2 cup water. Pressure cook for 5-6 whistles. Switch off the flame and let the pressure release naturally. If the keema looks a bit watery, cook till all the water has evaporated and the keema is dry.
In the meanwhile, soak onions in the vinegar and leave them in a refrigerator for at least half an hour to pickle them.
Once ready to assemble the burgers, cook the eggs sunny side up in the butter to your taste. I love cooking my eggs in my cast iron pan as the heat from the pan gives the crispest edges.
To assemble the burgers, slice the buns in half, spoon 1/4 cup keema mixture in between the buns, top with pickled onions, a fried egg and a few coriander leaves.
You may be left with extra keema, which can be refrigerated or cooled and frozen for up to a month.