Soak cashews in water for 10 mins.
Meanwhile, in pan on medium heat saute roughly chopped onions, garlic, ginger in 1 tbsp oil. Once the onions turn translucent, add the tomatoes too. Saute the mix for 2 more minutes and drain the water from the cashews and add them into the tomato mix. Stir and turn off the stove.
Once the mixture cools down, blend it into a smooth paste in a blender. Leave it aside.
In the same pan, or a new one on medium heat, add remaining 2 tbsp oil. Once the oil warms up, add the cumin seeds.
As soon as they splutter, add roughly chopped onions, saute for few seconds and add all the vegetables one by one – bell peppers, potatoes, carrots, cauliflower, peas, corn. Saute everything for few minutes until it turns slightly soft. Once the vegetables are almost cooked, add the blended sauce. Stir and add the spices. Stir everything and add some water to make it saucier. I added about ½ cup water.
Once it has good consistency. At this stage you can add the heavy cream or non-dairy cream. Mix everything and taste it. Crush some kasuri methi in your palms and add that too.
Garnish it with chopped cilantro and serve it with rice or naan.