If the action returns an HttpResponseMessage, Web API converts the return value directly into an HTTP response message, using the properties of the HttpResponseMessage object to populate the response. This option gives you a lot of control over the response message. For example, the following controller action sets the Cache-Control header.
The Macchiato Defined. The macchiato (mah-key-AH-toe) is a cornerstone of Italian coffee culture, along with the espresso and cappuccino, among other coffee drinks. It's basically an espresso (served in a demitasse cup) with a small amount of foamed milk on top -- the name macchiato means marked.
Caramel Macchiato. The delicious, multi-layered Macchiato begins with milk steamed until it's stretched and smooth to bring out its natural sweetness and is topped by a dense, creamy foam. Then rich espresso is poured over and through the foam, where it mixes with the milk and creates a brown mark on top.