Bakery counters in Manhattan and Brooklyn are seeing a new addition this June: cosmic blondies. These dessert bars, topped with white chocolate ganache and edible glitter, have appeared at several bakeries since Memorial Day weekend. At Butter & Scotch in Crown Heights, a tray of the bars drew a steady stream of customers on Saturday afternoon. Each bar sells for $5.50, with staff noting a spike in orders from families and groups heading to Prospect Park.

The recipe, featured in a recent New York Times column, calls for a standard blondie base finished with pastel-colored ganache. The ganache is spread in thick, swirling patterns, then finished with metallic sprinkles and edible glitter. The result is a bar that stands out in bakery cases already crowded with classic brownies and cookies.

Pastry chef Maya Lin, who runs a small operation out of her Lower East Side apartment, said she began offering the bars after seeing social media demand rise last week. On Sunday morning, she sold out of two dozen bars within an hour via pre-orders. She plans to double production for the coming weekend.

With school still in session and summer camps about to begin, bakeries are targeting parents and caretakers looking for portable, festive snacks. The bars have also made appearances at graduation parties and rooftop gatherings, according to bakery managers. Several operators said they expect the trend to continue through the end of July, as the demand for colorful, easy-to-carry desserts increases with outdoor events.