Gluten Free Flour mix

Here is an easy substitute for flour that I have found. Actually I have found two different versions using the same ingredients in different quantities. I have used the first one the most. I like to make up a bunch of it and keep it in a container so that when ever I need it I already have some on hand.

#1:
2 cups rice flour
2/3 cup potato starch flour
1/3 tapioca flour

#2:
2 cups rice flour
1/2 cup potato starch flour
1/2 cup tapioca flour

Either one of these you can substitute 1 to 1 in any recipe using flour. You will need to add 1 teaspoon xanthan gum for every cup of flour mix.