Soak 1C whole black urad dal and 1/3 C Rajma preferably overnight. Next morning, rinse well and add to a pressure cooker along with 5 cups of water, 1 tsp salt and 1 whole black cardamom. Pressure cook until soft and cooked completely.
Once the steam is released, gently smash the boiled lentils and leave as such in the pressure cooker or transfer to another wide bottomed cooking pan.
With the flame on, add 1.5 C puréed ripe tomatoes, 1 tbsp each ginger and garlic pastes, 2 tsp Kashmiri red chili powder and 2-3 tbsp butter.
Keep cooking and stirring every now & then on low flame for up to 45-50 minutes. Slow cooking is a must here for a good dal makhni as we all know.(Optional - mid way you can add 1-2 tbsp of store bought tomato paste and stir)
After about 45 min, in a separate pan, heat 1 tbsp butter, add 2-3 smashed & finely chopped garlic cloves and let them brown a bit. Add 1 tsp Kashmiri chili powder, mix well and transfer to the cooking dal immediately. Be careful to not burn the chili.
Give the dal a good mix and keep simmering for another 15 min. If you feel the dal has thickened, feel free to add in about 1/2-1 cup hot water and simmer for another 10 minutes.
Towards the end, add about 1/4 tsp of good quality garam masala and 1-2 tbsp cream/ whole milk and simmer for 5 more minutes.
Stir well and the dal is ready to be served hot with rice/ parathas/ nan. Add a dollop of ghee/ butter towards the end while serving.