The author pairs Nuxt 3 with TailwindCSS and Supabase to create a newsletter subscription form. They start by creating a new Nuxt 3 project using the nuxi CLI tool, then install TailwindCSS and set it up with a configuration file. Next, they add Supabase as a database solution and create an API route to save user data to the database. The author then creates a simple newsletter form with TailwindCSS classes and uses JavaScript to collect the email address from the form and send it to the API route for saving to the database. Finally, they provide instructions on how to set up the project, including environment variables for Supabase authentication and a demo of the completed project.