Boil water as required in a pot, and add mushrooms after slicing them in half and cleaning them.
Cook them for 10 minutes on high flame, strain them, and keep them aside for further use.
Heat oil in a skillet, add cumin seeds, and ginger-garlic paste (beat ginger, garlic, and green chilies in a mortar and pestle), and saute well.
Add chopped onions, and saute till it gets translucent. Now add turmeric powder, red chili powder, and coriander powder, and mix well. Add a splash of water to avoid burning.
Add chopped tomatoes, and salt, and sweat them. Then pour tomato puree and cook it on medium flame till the oil separates.
In a separate skillet, heat oil, and sear mushrooms and cauliflower on high flame till they get brown. Then add diced onion, capsicum, and tomato, and saute them for 30 seconds on high flame.
Combine the masala with mushroom and cauliflower and mix well. Pour water on them, and cover and cook it for 10 minutes on low flame.
Finish the recipe by adding kadai masala powder, and coriander leaves.
Your cauliflower and mushroom curry is ready to serve.