The Non-Canon Expert explains the circumstances in which Mace Windu joined the Jedi Order, not through the typical means of the actions of the Order’s Acquisition Division, but the legacy of Mace’s homeworld of Haruun Kal and the Korunnai.
This is a Legends story for Mace Windu with information found in a few Legends comics and materials, but primarily within the Jedi vs. Sith: The Essential Guide to the Force. I hope that you enjoy it!