1/2 cup sorghum flour
1/4 cup tapioca flour, plus more for your hands
3/4 teaspoon baking powder
1/2 teaspoon xanthan gum
1/8 teaspoon salt
6 tablespoons cooked, pureed spinach
1/2 tablespoon extra-virgin olive oil
2 tablespoons kalamata olives, chopped
1 tablespoon caraway seeds

Preheat the oven to 325 degrees F. Line a baking sheet with parchment paper.

Put the sorghum flour, tapioca flour, baking powder, xanthan gum, and salt in a bowl. Whisk to combine.

Put the spinach and olive oil in the bowl of a stand mixer or in a large bowl. Beat on medium speed until combined. Add the flour mixture. Beat until well mixed. Add the olives and caraway seeds, beating until combined.

Dust your hands with tapioca flour, and transfer the dough to the prepared baking sheet. Use your hands to make a log, about 2 inches wide, 1 inch high, and 12 inches long. Bake for 25 minutes.

Carefully transfer the log to a wire rack and cool for 10 minutes. Decrease the oven temperature to 300 degrees F. Using a sharp knife, cut the log into 1/2-inch thick slices, making about 22 in total. Put each piece, cut-side down, back onto the baking sheet. Bake for 10 minutes, until firm (but slightly soft) to the touch. Flip the pieces and bake for 5 to 10 minutes more, until nearly firm to the touch. Let cool completely on the pan.

The pieces should firm completely once they are cool, but if they aren’t crispy enough, biscotti is forgiving–just put them back in the oven and bake at 300 for 10 to 15 minutes.