In a large bowl combine all of your dry ingredients. Whisk them together well. Candied ginger rocks my socks. A hint for chopping it, take out the pieces you need and let them air dry for a while. They won't stick together as much and end up lovely like below.
Mix your sour cream and baking soda together and let it poof up.
Cut your butter into the flour mixture well.
Stir in that heavenly, rocks my socks candied ginger. Mix it in, then add your beaten egg and sour cream. Combine well, then turn out onto a floured surface.
Roll your dough into a log like below. Then cut the log into three pieces. Take each of those three pieces and turn them onto their cut side. Then proceed to flatten out with your hand and you honestly get these fantastic, perfect circles. Then slice each circle into 6 pieces.
Place on a well greased baking sheet and bake in a 350 degree oven for 15-20 minutes, until they are browned and gorgeous. And make a pot of tea right about now, sit down and have one hot from the oven.