All-purpose GF flour mix recipe
(double or triple all measurements to make a bigger supply of this flour mix that substitutes well for most flour in baked goods)... I like Bob's Red Mill GF products. Xanthan gum is pricey but a bag lasts a long time. You can also get just the amount you want in the bulk container of herbs and spices at most specialty grocers... I bought a couple tsps worth at Whole Foods (in with their whole leave teas and herbs) for about 50 cents.
2 c. rice flour
2/3 cup potato starch
1/3 cup tapioca flour
1 tsp. xanthan gum