Blend the cashews and coconut milk with 1 cup water into a very smooth paste. Set aside.
Heat 1 teaspoon of coconut oil in a saucepan. Add the onions and ginger-garlic paste and saute until the onions turn transparent but not brown. Add a couple of tablespoons of water if the ginger-garlic paste starts to stick.
Transfer the onions to a blender, add ½ cup water and the chili peppers and blend into a smooth paste.
In the same saucepan, heat the remaining teaspoon of coconut oil. Add the blended paste, mix, and bring it to a simmer.
Add the cauliflower florets and ½ cup water along with the cardamom powder, pepper, chat masala, and kasoori methi.
Stir well to mix, bring to a boil, and cover with a lid. Cook on a medium-low flame, stirring occasionally, for 10-15 minutes or until the cauliflower is tender but still has a bite. If you like your cauliflower softer, continue to cook a little longer.
Add the cashew-coconut cream and stir well to mix. Add water if the mixture is too thick, and thin it out to your liking. I like this curry rather thick and creamy.
Once the curry comes to a boil, add salt to taste and turn off the heat. Stir in lemon juice. Serve hot.