Pre-heat oven to 350 degrees and spray donut pan with cooking spray.
Whisk together flour, baking powder, salt, and granulated sugar in a large bowl.
In a separate small bowl, whisk egg with milk, melted butter, and vanilla.
Gently stir wet ingredients into dry ingredients taking care not to over-mix. Fold in cranberries.
Fill cavities of doughnut pan about ¾ of the way with batter and bake for about 9-11 minutes, until doughnuts are cooked through and light and springy to the touch.
Let cool in pan for a couple minutes before removing to wire rack to cool completely.
Once cool, dip doughnuts in matcha icing and top with sugared cranberries, mint and confectioners' sugar, if desired.