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I have found xanthan gum to be unnecessary with Bette Hagman's gluten-free
flour, which we make with one bag of Goya Rice Flour, 1 and 2/3 c. potato
starch flour, and 5/6 c. tapioca flour.  The King Arthur catalogue is
celiac-friendly.  A fes few tablespoons of mashed potato, mashed sweet
potato, fruit butter, or pureed dried apricots will often do the sticky
trick as well.
 
Good luck,
Elizabeth