Carla “Cookie Monster” Esparza is a professional mixed martial artist and the former two-time UFC Strawweight champion–the first of her weight class to do so.

Born in Redondo Beach, California, to parents of Mexican and Irish ancestry, Esparza’s foray into the world of martial arts began when she wrestled for her varsity team at Redondo Union High School. After graduation, she pursued MMA at the collegiate level and trained extensively in Brazilian Jiu-Jitsu. Needless to say, she was a natural; by 2010, Esparza had officially made her pro debut. With just three MMA fights under her belt that year, Esparza was selected last-minute by Bellator MMA to replace Angela Magaña in the highly-anticipated fight against the #1 pound-for-pound female MMA fighter in the world at the time, Megumi Fujii. While Esparza lost that particular fight, her talent and fighting style–which features powerful, offensive wrestling moves–was simply undeniable.

Esparza won several fights after that. She has featured on the tournament show The Ultimate Fighter and won the inaugural UFC Strawweight championship, a title Esparza would defend once more before experiencing complications with her shoulder. But at the peak of her reign, Esparza was considered the world’s #1 Strawweight champion–making Esparza both a UFC pioneer and icon.

Oh, and as for her nickname? It was given to her by her longtime coach Colin Oyama, who noticed Esparza had a predilection for sneaking treats at the gym during training.

“Kids love it. They’re, like, ‘I don’t know what you do. I think you punch people or something. But your name is Cookie Monster. You’re awesome,'” she said.