Making morning muffins for health-conscious house-guests in a few hours... I want to use my spelt muffin recipe which calls for 1 part whole spelt flour (which I have) and 1 part white spelt flour. I am out of white spelt flour, but have white rice flour and potato starch flour. Can I use either of these as a substitute? Other flours I have on hand: garbanzo and fava flour, buckwheat, ground flaxseed meal, almond flour. I also have xanthan gum. Any help would be GREATLY appreciated.