Ground cinnamon has a bolder flavor than whole cinnamon sticks do, and it releases that flavor more quickly. Accordingly, the powdered spice is best suited to quick-cooking foods; it can also be used toward the end of cooking to add zing to a dish. A whole cinnamon stick, on the other hand, is slow to give up its perfume, which tends to come through as a subtle accent rather than a dominant flavor. Cinnamon sticks work well in braised dishes like Indonesian chicken curry and in drinks like spiced wine, in which ground cinnamon would overpower other flavors. Finally, keep in mind that fat—whether it's butter, cooking oil, or the marbling on a piece of meat—helps activate cinnamon's flavor and also keeps that flavor from dissipating as a dish cooks. That's one reason why cinnamon performs well in butter-rich baked goods. It's also the principle behind the Indian technique called tarka: frying spices like whole cinnamon in clarified butter or oil to impart flavor to the fat before cooking with it.