Football Field Edible Icing Cake Sheet. Printed on rectangular icing made to fit 1/4 slab sheet cake. We use high-quality, food-grade ink to ensure that your Photo Edible Cake Decoration has true, vibrant colors. You can even order ahead of time, because the product is freeze-thaw stable. To apply, simply remove the plastic backing and place the Edible Cake Decoration on any store-bought or homemade quarter size sheet cake. Transforming your confection into a photo masterpiece will be a piece of cake.