Cocoa powder is prepared from the beans of the cacao tree. The beans are fermented, roasted and cracked before the cocoa butter is extracted, leaving a dark brown paste which is dried and ground into cocoa powder.
It is used in making everything from baked goods to savoury dishes. It is a key ingredient in preparing chocolate confectioneries, chocolate cakes, chocolate drinks and any other chocolate based goodies like choco flakes, choco chips and cookies.
You can dissolve the cocoa powder in milk, warm water or use as it is according to the method of preparation mentioned in your recipe.