In a saucepan, add tomatoes and cashews with water. Simmer it for about 15 minutes until everything softens. Once it is cooled, drain the water (reserve it) and grind the ingredients to a very smooth paste.
In a kadai, with little oil saute the mushrooms until it softens. Keep it aside.
In a kadai, heat butter. Add the bay leaf , green chillies, ginger and the ground mix. Keeping it on medium flame, stirring in between, let it reduce and thicken. Once the oil starts separating on the sides, add the garam masala and chilli powder. Mix it well.
Add water, the mushrooms and let the gravy boil for another 5-6 minutes.
Just before turning off the flame add the kasuri methi, ½ tablespoon Butter, cream and coriander leaves. While serving, add the ginger juliennes.