read how to measure flour

Single Batch (about 3 cups)

1 1/4 cups brown rice flour*
3/4 cup sorghum flour
2/3 cup cornstarch (or tapioca starch)
1/4 cup potato starch
1 tbsp + 1 tsp potato flour

*When I double the batch in a ziplock I will mix the first batch with brown rice flour and the second batch with sweet white rice flour. I read that the sweet white rice flour lightens and binds baked goods.

Good article on gluten free flours

A substitution guide and other flour blend ideas