Preheat the oven to 425°F/220°C. Line a muffin pan with 12 liners.
Whisk together the flour, baking powder, baking soda, salt, and cinnamon in a medium bowl or jug.
In the bowl of a stand mixer fitted with the paddle attachment, add the sugar, butter, eggs, vanilla and buttermilk then beat on medium speed
Pour the dry ingredients into the wet and beat until combined on low speed. Increase the speed to medium and beat until the muffin batter is almost smooth.
Keep a handful of cranberries to the side, then fold in the remaining cranberries and white chocolate chips.
Fill the liners to the top with the batter. Sprinkle over the sparkling sugar and add a few cranberries to the top of each muffin.
Bake for 5 minutes. Then, without opening the door, reduce the oven temperature to 350°F/175°C and bake for an extra 16-18 minutes.
Allow them to cool completely.