Every year during the holidays, I bake a batch of Mexican Wedding Cookies to share with friends and family. They’re so tasty, yet so simple: Just walnuts, flour, butter (or vegan buttery spread), and sugar. It was that last ingredient that tripped me up this year; my recipe called not just for regular granulated sugar, but the powdered variety, too. I’d already begun measuring the ingredients and preheating the oven when I realized I’d forgotten to buy powdered sugar.