Wash and soak black gram and red kidney beans in water for 8 hours, or up to overnight.
Turn on saute mode. Add butter (or oil) and let it heat up. Add cumin seeds and wait for them to sizzle.
Add onions and saute for 3 minutes, until translucent. Add green chiles, ginger, and garlic paste and saute another minute. Now add pureed tomato, spices, cilantro, kasoori methi, and stir well.
Add the strained lentils and water, and deglaze the pot by scrapping off any brown bits at the bottom of the pot.
Close the lid and set vent to sealing position. Pressure cook for 30 mins on Bean/Chili or Manual mode, at high pressure. After the cooking time is up, let the pressure release naturally for 10 minutes, followed by a quick pressure release. Open the lid after the pin drops.
Mash & Simmer
Select Saute and adjust it to 'low'. Using a potato masher, mash a few beans to make the curry naturally creamy. Sprinkle garam masala, add heavy cream and butter, and let the dal simmer for 10 minutes, stirring every 2-3 minutes.
If the dal starts thickening, add a few tablespoons of warm water. Dal makhani is ready when it turns deep red in color. At this point garnish with cilantro and serve!If you want a restaurant-style 'slow-cooked' taste, stir in ¼-⅓ cup warm water and simmer for another 10 minutes.
Optional: Dhungar Method for Dhaba-Style 'Smoky' Taste
Place a trivet in the Instant Pot over the dal. Place a small steel bowl over it. Now, using tongs, heat a small piece of charcoal on the stove directly over the flame until it becomes hot. Keep turning the charcoal so it heats evenly.
Place the hot charcoal in the small bowl and pour ½ teaspoon of oil on it. It will start smoking. Cover the pot with the lid and let the smoke get infused in the dal makhani for about a minute. After that, remove the bowl, stir the dal and enjoy!
No-Soak Method: If you want to skip the soaking process, rinse and drain the lentils and add them as per the recipe. Adjust the pressure cooking time to 45 minutes, followed by a natural release of pressure.
Slow-Cooked Taste: For a restaurant-style 'slow-cooked' taste, follow the extra step to simmer the lentils after pressure cooking.
Dhungar Method: This optional step adds a smoky taste to the lentils, giving them an authentic Dhaba-style taste. Since you only need a small piece of coal, ask a friend or neighbor who has a charcoal BBQ. Make sure that the coal is not treated with lighter fluid though.
Canned Lentils & Beans: If using canned lentils and kidney beans, reduce the pressure cooking time to 5 minutes, followed by a 5 minute natural pressure release.
Note: The nutrition facts below are my estimates. If you are following any diet plan, I recommend cross-checking with your preferred nutrition calculator.