This blog post provides a step-by-step guide to integrating Amazon Cognito authentication with a Hosted UI in an ASP.NET Core application. The author, Tom Moore, outlines the process of creating a new ASP.NET Core web application, setting up a Cognito user pool, and integrating the user pool with the application using Open ID Connect. The tutorial covers the creation of a custom Cognito domain, configuration of IAM roles for sending SMS messages, and the integration of the Cognito authentication system with the ASP.NET Core application. The author also provides guidance on testing the login functionality and cleaning up the Cognito user pool when no longer needed. Throughout the tutorial, Tom Moore shares his expertise on using Amazon Web Services (AWS) and .NET to build scalable and resilient applications.