Stir together dry baking mix, chili powder, red pepper, dried chili peppers, and cheese. Add sourdough starter and mix until moistened. Place mixture on a floured surface. Knead lightly and pat to 1/2in thick. Cut with a 2 1/2in cutter. Put biscuits in a greased pan and bake in cardboard oven for 20 to 25 minutes.