A Peruvian custom is to include wedding charms between the layers of the wedding cake, attached with ribbons. Before the cake is cut and served to the guests, each single woman pulls a string. This works, of course, if you have a small number of single women attending the wedding. (In several of the bridal magazines you will see ads for these charms.) The one who pulls the ribbon with the ‘ring’ on the end is the next one to marry within a year.
We found this lovely article and photo, that may be of interest to you! Peruvian Wedding Cake