Cream together brown sugar and applesauce. Add egg and mix well. Then, add in the milk and vanilla.
Mix the flours, xanthan gum, baking soda and salt together and add to the creamed mixture.
Stir in the rhubarb and strawberries.
Fill lined or greased muffins tins ⅔ full. Bake at 350 for 25- 30 minutes or until an inserted toothpick comes out clean. Makes approximately 20 muffins.
Recipe by Premeditated Leftovers™ at https://premeditatedleftovers.com/?p=15469