Wicked is the prequel to the Wizard of Oz, depicting how all of the characters met. In this episode, Mindy makes reference to Wicked and how she doesn't care how characters came to meet, which is essentially what this episode is all about.
Mindy tells Danny she "needs to work with people she's friends with. Who do happy hour and Secret Santa." This describes the basis of her most famous role as part of The Office.