"Crystallized ginger" refers to fresh ginger that has been cooked in sugar syrup and then dried. This process makes the ginger sweeter, chewy, and with a slightly crunchy texture. Full definition
These biscotti are also great with a 1/4 cup finely chopped crystallized ginger added to the batter before stirring in the flour. (baked-theblog.com)
Although I didn't actually make anything from their cookbook, I was definitely inspired by the use of crystallized ginger in their Pucker - Up Lemon - Limeade. (girlcooksworld.com)
On Saturday I baked a Glazed Cranberry Quick Bread with crystallized ginger for my dad's birthday. (cookincanuck.com)