1. Place the blueberries in a bowl.
2. Add the boiling water and vinegar, stirring to combine.
3. Allow to cool for about 10 minutes, strain the dye, then add 3-4 freshly-cooked hard-boiled eggs.
4. Place the bowl in the refrigerator; leave eggs in the dye for as little as 1 hour or as many as 12, until desired color hue is achieved.
5. Remove eggs from the dye with a slotted spoon and place on a rack in the fridge to dry.

**To hard-boil eggs: Place eggs in a pot. Cover with about 1 inch of cool water. Bring to a boil over high heat; immediately remove from heat, cover, and set a timer for 15 minutes. After 15 minutes, remove lid and run cool water over the eggs to halt cooking.**