I had the great opportunity to speak at the user group that I happen to be the co-leader and co-founder (Omaha PowerShell User Group) of last week talking about PowerShell and Pester. This was the result of my own call for topics as I was going to speak about something, but wanted to leave it up to my fellow attendees to help determine the topic. Pester was the overwhelming majority, which was great for me because I wanted to get more into this as well!
I also had a lot of input online about recording this (we usually only record for remote speakers as my laptop is somewhat old) and that is also available to view as well.
Pester is a great framework to learn and understand and it is something that you will definitely not regret learning as you can start applying it to existing scripts and modules in your environment!
Video
Slide Deck and Example Code