1Heat oven to 350°F. Spray bottom only of 13x9-inch pan with baking spray with flour (do not use dark or nonstick pan). In large bowl, beat cake mix, margarita mix, oil, water, lime peel, eggs and 1 cup of the diced mango with electric mixer on low speed 30 seconds, then on medium speed 2 minutes, scraping bowl occasionally. Pour into pan.
2Bake 32 to 36 minutes or until toothpick inserted in center comes out clean. Cool completely, about 1 hour.
3In small bowl, place remaining diced mango and mash with fork until pureed. In medium bowl, fold together whipped topping and yogurt; frost cake. Spoon small dollops of pureed mango over frosting, then swirl with back of spoon. Store in refrigerator.