Store asp WebAPI bearer tokens in the database

I have a desperate need to store the bearer access_tokens in the database immediately they are produced before they are sent to the user...I am using an example from http://ift.tt/1gUyYFU to implement the authorization... How do I catch the token immediately it is created within the method "public override async Task GrantResourceOwnerCrede ntials ( OAuthGrantResourceOwne rCredentialsContext context )"

It's important to note that I implicitly understand the downfalls of doing things, but it's necessary