When I don't have curry powder can I use garam masala as a substitute? Can it give the same taste as curry powder or not? If use garam masala how much should be added?
No, you won't get the same flavor or color. Curry powder is a blend of turmeric, cumin, coriander, and sometimes fenugreek, black pepper, mustard or cardamom. Curry powder is generally added towards the beginning of a recipe and cooked with the food.
Garam masala is a finishing spice blend shares some of the ingredients of curry powder (cumin and coriander) but is significantly different in that generally has cinnamon, bay leaves, fennel seed and cloves. Garam masala has many aromatic spices in it, and it is generally added towards the end of a recipe to give it an aromatic punch.