Sparkle cookies are made with cracker dough containing no sugar. Instead of rolling the dough out on flour, you roll the dough out on sanding sugar. The crunchy sanding sugar becomes embedded into the cookies, creating visual appeal and a sugary sweet crunch. I know that I'll be pulling this recipe from the files (looking it up on the blog) again and again to revisit the buttery caramel-like crisp pleasure they bring - especially because my mother-in-law just declared them her new favorite cookie.
Some versions of this recipe call for the addition of a couple drops of lemon oil. I did not add this, but it would be worth trying.