These are a variation on the classic Black and White Cookie. Black and white cookies are actually thin flat cakes that are popular at Jewish delis, and I've loved them since childhood because of how soft they are. The cookies themselves are typically flavored with vanilla as well as something tangy, like buttermilk or sour cream, and some lemon which brightens them up under their thick blankets of glaze. They have such great personality, and I love both sides equally.