Combine the butter, unsweetened chocolate, and chili powder in a medium bowl and set over a pot of barely simmering water. Make sure that the bowl doesn’t touch the water. Stir until melted, then remove the bowl from the heat. Whisk in the sugar, eggs, and vanilla.
Mix together the flours, baking powder, cinnamon, black pepper, salt, and xanthan gum in a small bowl. Add the flour mixture to the chocolate mixture, then stir until just incorporated. Fold in the chocolate chips and raisins. Form the dough into a large mound, wrap it in plastic wrap, and refrigerate for 2 hours or until firm. The dough can also be refrigerated for up to 3 days.
Preheat the oven to 350° F and line two baking sheets with parchment paper. Combine the sugar and cinnamon in a medium bowl to make the coating.
Remove the dough from the refrigerator and form it into 1 inch-wide balls (each should be about a tablespoon). Roll the balls in the sugar mixture, then place them 1 inch apart on the cookie sheets.
Bake the cookies until they are puffy and cracked, about 12 to 15 minutes. They should not spread too much. Transfer them to a wire rack and allow them to cool completely.