Then add butter into the pan and add whole garam masala. Thereafter add onion, all masalas and stir fry for 2 minutes until it become golden brown. Then add chopped mushrooms and fry it for 1 minute. Add cashew and tomato paste. Thereafter add salt and sugar. Mix it and cook it for 2 minutes. Also add 1 cup of milk, simmer the heat and cook it in low flame. Stir frequently