In a medium bowl, whisk together ¾ cup sugar, the orange zest, and salt until well combined. The zest should be evenly distributed—no clumps of pure orange peel.
Add the cranberries to the sugar mixture and toss gently with a rubber spatula until every berry is thoroughly coated. The berries should look like little red jewels now.
Transfer to a parchment-lined baking sheet in a single layer, spacing them about an inch apart so they don't stick together as they dry.
Sprinkle the remaining ¼ cup sugar evenly over the cranberries for extra crunch. Set aside at room temperature for 24 hours—no need to refrigerate yet.
After 24 hours, give them a good shake on the parchment and drizzle with vanilla extract. Toss one final time until the liquid is absorbed and the berries have that beautiful sugared crust.
Store in an airtight container at room temperature for up to 1 week (or refrigerate for longer storage).
