The recent tutorial on D4Drupal, "Behat testing in Drupal 10, Drupal 9, Drupal 8", introduces viewers to the application of Behat Testing, an open-source PHP framework that enables automated testing through Behavior Development in Drupal. The video by Saranya Ashokkumar details setting up the Drupal extension for the Behat Testing Library, creating feature files and context classes to define test scenarios and test the Drupal site's functionality, and incorporating custom testing steps using the context file. Additionally, it demonstrates the creation and execution of basic test scenarios in a Drupal instance, providing insights into executing specific feature files and setting up automated testing on different instances by providing base URLs.