From Maida Heatter's Brand New Book of Great Cookies, adapted gluten-free.
1 c chopped crystallized ginger
3 c rice flour mix
3/4 t xanthan gum
3/4 t baking soda
1 t baking powder
1/4 t salt
1 1/4 t finely ground pepper (I used black because I didn't have white, but the recipe says white)
1 t ground ginger
1/2 t cinnamon
1/2 t mustard powder (seriously!)
1/4 t ground cloves
1/2 c sugar
1 c chopped crystallized ginger (I use this brand)
1/2 c honey
Mix together the flour mix, xanthan gum, baking soda, baking powder, salt, pepper, ground ginger, cinnamon, mustard, cloves and sugar. Stir in the crystallized ginger. Mix together the eggs and honey (this will take a minute, the honey will not want to cooperate), then stir into the dry ingredients. Mix by hand until everything is completely moistened. Spray two pieces of plastic wrap (about a foot and a half long each) with a buttery spray, then plop dough by tablespoons into a line on each piece of plastic wrap about a foot long. Wrap up the sides and fold over, then twist the ends around. Place your wrapped logs of dough in the freezer for about an hour or two or overnight. If you want, you can keep one in the freezer for quite a while, if you don't want to make all the biscotti at once.
Later, once your dough has been in the freezer for a while, preheat the oven to 300. Line two baking sheets with parchment paper or foil or a silpat, then turn out your lines of dough onto each. Adjust the oven racks to divide the oven into thirds. Bake the dough logs 45-50 minutes, rotating halfway through. Your logs will turn quite dark when done.
Reduce the oven temp to 275, then slice the dough into thin logs using a sharp serrated knife. Slice on the diagonal about 1/4 to 1/3" wide (yes, skinny!), then place lying down on your cookie sheets. Bake at 275 for 25 minutes, turning once.
These are good and crunchy, but mellow out a bit in flavor when you dip them in your morning coffee and soften up a bit. I like them both ways.