In a large saucepan, bring the water, sugar and vanilla to a simmer stirring until dissolved.
Turn off the heat and add the cranberries tossing with a wooden spoon to coat. Allow the cranberries to sit in the simple syrup for 5 minutes and then transfer to a wire rack.
Allow the cranberries to dry for 20-30 minutes.
Pour some sugar in a shallow dish and roll the cranberries in the sugar to coat completely.
Transfer to a baking sheet lined with parchment and allow to dry completely, approximately 1 hour.
Store in an airtight container for up to 48 hours.
Notes
Sugared Cranberries are best served within 3 days.