Shhhhh.... Joe and Sophia are working on an exciting project together. It's PROBABLY a course. It's PROBABLY going to live on Udemy. It's DEFINITELY going to be amazing.
The original OOUX manifesto. You'll learn why designing "objects first" is pivotal and how it helps you define the core structure of your system. The process has evolved over the years into Sophia's ORCA process, but this 2015 article is still a great place to start.