Makes about 2 cups (270 grams) / This mixture also works well for gluten-free cookies. You can vary the mixture of flours and starches; however, your choice may change the final result (rice flour, for example, may make brownies more grainy). Sticky potato starch differs from potato flour—the starch is made without the skin and is not cooked, while potato flour is made with the whole potato and is cooked. Both are available in natural products stores. If you’re using measuring cups instead of a kitchen scale for the sorghum flour and potato starch, be sure to pack down each ingredient into the cup, and scrape out all flours (especially tapioca and potato starch) thoroughly with a spatula.