Sweet Potato Walnut Sourdough Muffins

• 1 cup sourdough
• 1 egg
• 1/2 cup sweet potato
• 1/4 cup milk, to thin (if needed)
• 1/4 cup coconut oil
• 1/4 cup honey
• 1 teaspoon vanilla
• 1/2 cup whole wheat flour
• 1/4 cup oat flour
• 1 teaspoon cinnamon
• 1 teaspoon baking soda
• 1/2 teaspoon sea salt
• 1/2 cup walnut pieces

Mix sourdough starter, egg, sweet potato, milk (if using), oil,  honey, and vanilla together in medium bowl.  Mix dry ingredients separately and add to wet ingredients, mixing only enough to moisten.  Add walnuts and pour into well greased muffin pan.  Bake at 350F for 15-20 minutes.  Makes 8 muffins.