Working with Cookies in Web API and HttpClient

ASP.NET applications often use cookies to store user specific pieces of information. Not just web forms and MVC applications, Web API too can use cookies. Sometimes developers device an authentication scheme revolving around cookie as an authentication ticket. Although this article won't show you how to develop such a scheme, it illustrates how cookies can be issued and used in Web API. Specifically you will learn: How to set cookies from a Web API controller and read those cookies in a client application and how to set cookies from a client application (HttpClient) and read those cookies in a Web API controller.

http://www.binaryintellect.net/articles/0f52c5bf-b7a4-4720-9572-6159b1804d1d.aspx