Our journey has come to an end, but fear not. You now are well equipped to enter the world as a TDD master.
You not only understand how to develop with a TDD mindset, you also know why TDD is so important to develop testable, extensible, and maintainable software applications. Your IDE is set up to test C# and/or JavaScript applications and you have a continuous feedback loop on the quality of your software.
You understand the importance of defining and testing the boundaries of an application and the benefits of abstracting away third-party code (including the .NET Framework). Spies, mocks, and fakes, and how best to employ them are now well understood.
Approaching a green-field application with TDD is mind should now be almost trivial. Take the broader problem of the overall application and break it into meaningful chunks that can be developed...