Start with roasting the spices for the base of the curry for few seconds until the aroma is felt. Afterwards blend all the spices in a blender, make it into smooth powder form.
Add the spice powder mixture in a bowl + concentrated tomatoes paste + 1 ½ cups of water for the base of the curry + mix it well and keep it aside.
Add butter + oil in a pan, add onions + spring onions (white part) ginger shreds + ginger garlic paste + sauté for few seconds.
Add the spice and concentrated tomato mixture to the pan, now add turmeric + coriander powder + chilli powder (optional green chilli ) + salt. Mix it. Cover it with a lid for 5 -10 minutes on medium high heat, stir it occasionally. Cook it until the quantity starts reducing and leaves little bit of oil.
Add mushroom + corn + squash, cook it for few minutes until mushroom turns soft. Now add green part of spring onions and all 3 chopped peppers and coconut milk, cook for 8 minutes, stir it occasionally.
Taste the seasoning, add salt if required, garnish it with fresh chopped coriander leave, serve hot with rice or any Indian bread.
Add Indian Cottage cheese if you like in this curry.