Heat up a dutch oven on medium heat, once hot, add oil, followed by cumin seeds, bay leaf, and black cardamom. Saute for a minute.
Add onions, green chilies, ginger, and garlic. Season lightly with salt. Cook down for 5-7 minutes until the onions are slightly brown.
Don't worry if the onions stick to the pan, it'll all come off. Add the following spices - red chili powder, Kashmiri red chili powder, turmeric powder, and coriander powder. Cook for 30 seconds.
Immediately add water to avoid the spices from burning. Also, deglaze the bottom of the pan.
Cook for a couple of minutes until all the water has evaporated
Add the tomato puree. Mix well.
Allow the tomatoes to cook for a couple of minutes. Season with a little salt.
Cover and cook for 20 minutes on low-medium heat.
Your masala is ready.
Add all the cooked rajma along with the liquid to the masala mixture.
Cover and cook for 15 minutes on low-medium heat.
Mash the beans slightly - this will give the rajma a thicker consistency. Turn off the stove.
Add amchur (mango powder), dry Kasoori methi, garam masala, and fresh cilantro.
Stir. Let the Rajma Masala sit for at least 15 minutes before serving. This allows the flavors to combine.