the Best Gluten-Free Shortbread Historians date shortbread to medieval times. The first printed version appeared in 1736! Made with flour and butter, expensive ingredients, it was often reserved for Yuletide. To this day, Walkers sells more shortbread during the holiday season than any other time of year. gluten-free shortbread store really well in an airtight container for a ridiculously long time! enjoy them now, next week or the week after!