"There are flours made from a variety of other sources besides wheat, including white or brown rice, potatoes, beans and sweet potatoes. Johnson's "flour" is a mix of rice, potato starch and tapioca flours. For artisan breads she may use brown rice flour or millet. She uses xanthan gum or guar gum as a gluten substitute. Gluten is what makes cakes and breads light and airy."
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