I need some ideas for a Mexican dessert?

We're going to have an end-of-the-year fiesta in my Spanish class, and I'm particularly good at baking dessert so I want to bring in a dessert. I really like Mexican food so hopefully a Mexican dessert, although Spanish works too. I want it to be exotic though. Not just a cake with a few extra ingredients and the name "Mexican". For instance, in fifth grade we had an around-the-world end of the year party so I brought in Thai rice pudding. Something distinctly exotic. Ideas? Links? Recipes? Anything helps.