The urad dal and rajma needs to be soaked in 3-4 cups of water either for 6-8 hours or overnight
Have the instant pot on saute mode and add the oil
Once the oil is hot, add the ginger & garlic
Saute for 15 secs or so till you smell the release of the aroma and add the onions
Saute the onions till they become translucent, for a couple of minutes
Next add the tomatoes and saute for 2-4 minutes
Cancel the saute mode and once the mixture is cool, blend into a nice paste in a blender
Now turn the instant pot to saute mode again and once hot, add the butter
Now temper with cumin seeds and once they release the aroma in 15 secs or so, add the ground tomato onion mix
Next add the cumin powder, coriander powder, garam masala, turmeric powder, salt & the chilly powder
Give the mixture a nice stir and add the soaked dal and kidney beans along with the water
Now cancel the saute mode and set the instant pot to pressure cook on high for 30 minutes
Release the steam manually and after the steam is let out, open the instant pot and give the dal makhani a nice stir. If too thick, a little extra water can be added at this time in saute mode
Using a masher, gently mash some of the beans and lentils to get a cohesive mixture
Stir in the cream just before serving for a nice rich and creamy taste