I think this recipe from About.com works great, though I made tiny adjustments. Mix the wet ingredients. Mix the dry. Mix them together. I used one very large piece of candied ginger for a half batch. Bake at 375F. I dropped them by the 1 T onto sheets with three inches around and they cook pretty fast, maybe 7 minutes. Look at them after five: if they've started to get gold around the edges, take them out, let them stand on the sheet for five minutes, remove to a rack.
12 tablespoons unsalted butter, room temperature
1 1/2 cups granulated cane sugar
1 large egg
1 teaspoon lemon extract
2 cups gluten-free all purpose flour mix with xanthan gum or guar gum in the mix (I used Gluten-Free Pantry GF All Purpose Flour with added guar gum)
1/2 teaspoon gluten-free baking powder
1 teaspoon ground ginger
1/4 teaspoon salt
grated zest of 1 lemon
2 ounces minced crystallized ginger
(I used regular flour and had no baking powder so substituted baking soda in equal part: no problems).
