Preheat an oven to 350ºF. Line a sheet pan with parchment paper.
Mix together the flour, baking powder, baking soda, ground cardamom and salt.
Cut the cold butter into small pieces. Pulse the flour mixture and the butter in a food processor just until it looks like crumbs.
Add the ginger, sour cream and 1/2 cup of sugar and one egg and quickly pulse just to bring it together.
Remove the bowl from the food processor and using an ice cream scoop, scoop out 1/3 cup scoops and place on the prepared baking sheet.
Whisk the remaining egg with 4 teaspoons of sugar, and glaze each of the scones generously. If need be make another batch to make sure they are generously glazed.
Bake for 25 minutes, until golden brown
