An ASP.NET Core Web API for Azure AD B2C that shows how to protect your web api and accept B2C access tokens

There's a newer version of this sample taking advantage of the Microsoft identity platform

Check it out the TodoListService Web API of the ASP.NET Core Web app calling your own API for B2C sample

If you really need to access this sample, you can navigate to the master branch, but please know that it's no longer supported.