Soak cashew nuts in 2 tbsp warm water for 10 mins. Grind to a smooth paste and keep aside.
Crush together whole masala (cardamom, cloves, black pepper, fennel seeds & cinnamon).
Heat oil in a deep and wide pan. Add crushed whole masala and fry for 2 mins. Add chopped onion and cook till it becomes brown.
Add crushed ginger & garlic and green chilli. Fry for 2-3 mins, till the raw smell goes. Add coriander and turmeric powder. Fry for 2-3 mins. Add salt, cubed potato and carrot. Mix well.
Add medium thick coconut milk, mix and bring it to boil. Reduce flame to lowest and cover and cook for 10-12 mins. Add cauliflower florets and peas. Mix well and cover and cook for 8-10 mins. Add thick coconut milk, mix well. Simmer for 5 mins. Add cashew paste and mix well. Cook for another 4-5 mins and remove from fire.
Let the curry rest for half an hour for the flavour to settle in. Keep in mind, that the curry tends to thicken as it rests, so adjust the gravy accordingly.
Serve with Chapathi, Appam, Idiyappam, Puttu, Pathiri etc;
Notes
I used boiled cauliflower florets here, hence I added it at a later stage. You can use frozen mixed veggies to make this curry. Also, you can add boiled eggs to this curry and make it an egg stew. You can also use chicken instead of veggies.