Curry Leaf (Murraya koenegii) refers to a purple-black fruited tree which is most famous for its aromatic leaves that provide curry spice. The leaves are used as an important food flavoring in Indian and Asian cuisine. When cooking, the leaves are generally used fresh direct from the tree. The yellow "curry powder" which are sold in the markets which is common in Western countries is actually not curry at all, but a mixture of several spices intended to mimic the true curry flavor. The yellow color comes from turmeric root.