This is a good and simple to make cookie. Soft and tasty. I suggest beating the sugars, egg and butter very well first, then adding the yogurt, then the flour gradually. The crystalized ginger, chopped very fine, adds a nice zing - I found mine at my natural foods store, sold by bulk weight, so I only had to buy as much as I needed. Next time, I'd even increase it to 2 Tablespoons, since I like the strong flavor bits throughout the cookie. I added the extra I had, and some powdered ginger, to the frosting. The frosting in the recipe to me was much too much in quantity and too thin. I suggest starting with 2 cups max of powdered sugar, and add yogurt until you get the thickness you like. After frosting, let them sit out several hours to harden the icing completely, making storing them much easier.