Combine sugar and water in a medium saucepan set over medium heat. Cook until the sugar dissolves. Bring to a simmer, about 3 to 4 minutes.
Add the orange zest and mix well. Switch off the heat. Set aside until it turns lukewarm. Check for the consistency of the syrup. It should be slightly thick and sticky.
Add the cranberries to the saucepan, stir to coat evenly with the syrup. Steep for 10 to 15 minutes. At this stage, you can proceed to the next step or you can let the syrup come to room temperature. Cover the saucepan and refrigerate overnight.
Line a baking tray with parchment paper. Strain the cranberries, transfer them to the prepared baking tray in a single layer.
Allow it to dry for 30-45 minutes or up to an hour if it is humid where you live.
Place granulated sugar in a shallow bowl or tray. Line another baking tray with parchment paper and set it aside. Toss a few cranberries in the sugar at a time and transfer them to the prepared tray.
Repeat until the rest of the cranberries are coated. Let stand for an hour or until dry.