On this Dinner: Impossible, Robert is in Puerto Rico to celebrate Quinceanera -- a young woman's sweet 15 birthday celebration. This is an important rite of passage in Latin culture. Robert has only nine hours to create a traditional Puerto Rican feast for 100 Quinceanera guests. But the highlight of the meal is an elaborate birthday cake, which Robert must also make. Can he master the meal and the cake, or will this be Dinner: Impossible?