Gwen Stefani and Blake Shelton challenged Jimmy Fallon to an epic lip sync battle on a recent episode of The Tonight Show Starring Jimmy Fallon. Each of the three contestants had to select two songs each in advance which were performed. Gwen Stefani proved that she still has the same on-stage moves that she had back in the 90s with No Doubt. Blake Shelton proved that he has a very diverse taste in music and Jimmy Fallon proved that he is a comical genius that is great with physical comedy as well as verbal impressions. However, when you see how Gwen Stefani and Blake Shelton won the competition, your jaw will drop to the floor!