Shortbread Cookies with Blueberry Sparkling Sugar
To make ahead: Store sparkling sugar (Steps 1-2) airtight at room temperature for up to 1 month. Store cookies airtight for up to 1 week or freeze for up to 1 month.
Equipment: Parchment paper
Tip: Freeze-Dried Fruit for Food Coloring
Freeze-dried fruits have all their water removed in a heat-free, vacuum process that also protects colors, keeps flavors fresh and fruity and creates a crumbly texture (unlike the leathery, traditionally dried ones). Ground into powder, they're ideal for coloring.
Where to Buy: Both freeze-dried fruit and pre-ground powders are readily available. Look for them at the supermarket with other dried fruit or online at amazon.com.
To Prepare Them: Grind freeze-dried fruits in a food processor until they become a fine powder. (If you find dried fruits already powdered, there's no need to grind them.)