Nalani's Whole Grain Flour Mix

6 cups whole grain 
 (Comprised of brown rice flour, sorghum flour, millet or buckwheat flour)
  For example...
 2 cups brown rice flour
 2 cups millet flour
 2 cups sorghum flour

3 cups white grain
1 1/2 cups white rice flour
3/4 cup Tapioca flour
3/4 cup potato starch

2 T xantham gum (generous) 

I use this straight across with good success in baking recipes.
See Nalani's Muffins for an example for this mix.  It can be used instead of flour, but you may need to tweak the recipe by adding more or less than normal straight flour.

Nalani Brown, INDY