You saw the video. A spoonful of shimmer goes into a mug, someone stirs, and the whole cup turns into a galaxy. So you tried edible glitter in coffee at home, and your cup just looked like coffee. Almost everyone...

Every jar on the shelf promises sparkle. The label rarely tells you which one will look right in a glass, and reviews do not settle it — five stars from somebody decorating cookies says nothing about a tall drink. So...