- Mix the flax meal with the water in a medium bowl. Set aside and let rest for about 5 minutes.
- Combine the oat flour, rice flour, almond flour, arrowroot, baking soda, ground ginger, cinnamon, salt, nutmeg, and xanthan gum in a large bowl and whisk until combined.
- Add the coconut oil, molasses, sugar, grated ginger, and vanilla to the flax mixture. Mix until combined. Add the wet ingredients to the dry ingredients and stir until combined. Chill the dough in the fridge for at least 30 minutes.
- Once you’re ready to bake, preheat the oven to 350°F. Line two baking sheets with parchment paper or silicone baking mats. Remove the dough from the refrigerator.
- To make the cinnamon sugar : Mix the sugar and cinnamon in a shallow bowl.
- Scoop out a tablespoon of dough and roll it into a ball. Roll the ball in the cinnamon-sugar mixture, then place on the prepared baking sheet. Repeat with the remaining dough, spacing the balls about 2 inches apart. Use a fork to gently flatten each cookie
- Bake for 10 to 12 minutes, until the cookies are spread out and firm around the edges. Let the cookies cool on the pan for a couple of minutes before transferring them to a cooling rack.
- Cool completely before serving. (They will firm up more as they cool.) Store in an airtight container at room temperature for up 4 days.
- VARIATION To make these cookies with gluten, replace the oat, brown rice, and almond flours with 1½ cups unbleached all-purpose flour and exclude the arrowroot powder and xanthan gum.