Place oil in a heavy bottomed small saucepan on medium heat.
Add bay leaves and green chilli. Sauté for a few seconds. Reduce heat to low and add kasoori methi and ginger garlic paste. Sauté for another few seconds until fragrant and starting to turn golden.
Add tomato passata, garam masala, cardamom, paprika, salt and rapadura sugar.
Cook for 8-10 minutes until the sauce has turned a shade darker and oil starts pooling around the edges.
Add coconut milk. Cover and simmer on low for approximately 20 minutes until rich and fragrant. If it starts to thicken a lot, add 1/4 cup water.
The sauce is ready to use at this point but I like to make it smoother by cooling it, removing the bay leaves and blending it briefly in a small food processor. The sauce is ready to be mixed with pre-cooked protein or roast veggies. It can also be packed away in freezer-safe containers or zip lock bags and will keep well in the freezer for up to two months.
Sugar - Rapadura Sugar can be substituted with brown sugar or maple syrup.Chilli - Paprika can be swapped with red chilli powder if you like your curry hotter.Ginger & Garlic - If you don't have ginger-garlic paste on hand, substitute with 1 tablespoon fresh grated ginger and 3 minced garlic cloves.Kasoori Methi - It is the Indian name for dried fenugreek leaves. It can be found in the dried herb and spice section of Indian supermarkets. Methi or Fenugreek is bitter and has a unique taste which makes this "Makhani Sauce" authentic. If you can't find fenugreek, try substituting with a teaspoon of mustard powder or Dijon mustard.