Mondelez International's Mallomars brand is celebrating its 100th anniversary with a Facebook-based user-generated content promotion that ties in with a sweepstakes. Fans of the marshmallow creme cookies are being invited to share their favorite “Mallo-Memories” by posting photos, videos and stories through the Mallo-Memory tab on the Mallomars Facebook page. Those who do will receive a $1 coupon on the cookies and can enter a Mallomars 100 Sweepstakes. The sweepstakes -- launching Sept. 23 -- offers a chance to win one of five monthly drawings for a $100 gift card, as well as the grand prize: a year’s supply of Mallomars and an "ultimate Mallomars prize pack." The effort is being supported with digital and social promotions and public relations. There will also be local in-store programs with specific retailers. Mallomars are sold seasonally, from September through March. The 2013 season kicked off during the week of Sept. 9. The seasonal availability originated because in 1913, when Nabisco launched the brand, there were physical challenges involved in shipping and displaying the chocolate-covered cookies during the hotter months. While today's shipping and storage methods have of course made such physical concerns passé, Mallomars continue to be sold during the cooler seasons to maintain tradition.