How to authenticate the JWT sent from the Microsoft Teams MessageCard HttpPost

[ToastyCeral]

Using Microsoft Teams MessageCard, I am able to utilize the HttpPost to send data to a ASP.Net Core service, but how do I authenticate the JWT with Azure Active Directory that is sent in the Authorization header? I know the JWT contains the logged-in AD user object id, but I cannot find any documentation on what to do once I have the value(s).

[Wajeed-msft]

Raise an issue here: #10835