Combine 200 grams sugar and water in a medium pot and bring to a simmer. Cook until sugar fully dissolves and remove from heat.
Let the simple syrup cool for 20 minutes, and then add the cranberries. Let cranberries sit for 5 minutes, and then strain the berries on a cooling rack set over a half sheet pan or piece of parchment. Let dry for 45 minutes, being sure to mostly separate the berries so they have room to dry.
Add 100 grams of sugar to a bowl, and then coat a few berries at at time until all berries are sugar coated.
Store sugared cranberries in an airtight container at room temperature for up to 3 days. Freeze remaining cranberries for up to 2 months if desired. (Re- role in sugar after thawing)
For a shortened method- add cranberries to syrup as soon as you remove syrup from the heat. Let the berries soak for 60 seconds, and then strain them. The main downside to this method is that the super hot syrup tends to make the berries burst slightly, so they may not be perfectly smooth and round afterward.
Save cranberry simple syrup for cocktails or mocktails.