Sprinkles aren't something that it had occurred to us to make at home until pastry chef Monica Glass of Philadelphia's Sbraga Dining showed up in our test kitchen, toting a bowl of pastel-colored, beautifully irregular bits. "You made these?" gasped everyone who wandered by, before immediately reaching in and stealing a pinch. Turns out, it's quite easy: sprinkles are really just a variation on royal icing, a stiff frosting made from beating egg whites and sugar. Glass adds a little coloring and flavoring, pipes thin lines on a sheet pan, and lets them air dry overnight. Once dry, she breaks the lines up into colorful little sprinkly bits to serve atop ice cream or cakes.
Glass flavors her sprinkles with a touch of vanilla extract, but you can use any flavoring you like—or just go plain. However you flavor them, the results will put those store-bought rainbow sprinkles in the plastic container to shame.