Soak rajma in water overnight or minimum 6 hours. Add Rajma with 3 cups of water in a pressure cooker and cook till kidney beans are soft and easily mash between fingers.
Heat a pan and add oil to it. When the oil is warm add cumin seeds, carom seeds and let it crackle. Add turmeric powder and mix.
Add onion and saute till translucent. Now add ginger and garlic and saute.
Add chopped tomatoes to it. Saute for few minutes till the tomatoes are nicely cooked and mushy.
Add 2 tbsp water, garam masala, red chilli powder and mix well.
Now add this gravy to cooked Rajma and salt and mix well. If you feel the gravy is too dry, add little more water. Close the cooker and give 1 whistle.
Garnish it with coriander leaves and serve it hot with rice or flat bread.