Preheat oven to 350F. Line two baking sheets with parchment paper, or grease them with butter.
Whisk together oat flour, arrowroot flour, cinnamon, baking powder, and salt.
With electric mixer, cream together butter and sugar. Beat in egg and vanilla. Slowly beat in the oat flour mixture. Stir in the oats and raisins.
Form dough into balls and press onto prepared baking sheets leaving room between each cookie for a little spreading. Bake for 15 minutes or until starting to brown around the edges. Allow to cool on baking sheet for a couple of minutes, then transfer to cooling rack.
Either coarse or fine oats will work in this recipe, according to personal preference.