Preheat oven to 375° F. Coat a 12-cup muffin pan with butter to prevent sticking.
In a medium bowl, combine whole wheat pastry flour, baking soda, salt, cinnamon, ginger, nutmeg and sugar.
In a large bowl, whisk together coconut oil, apple sauce, eggs, sweet potato, vanilla, milk and vinegar. Stir in the dry ingredients until just combined.
Pour the batter into the muffin pan and bake for 20 minutes or until a toothpick inserted into the center comes out clean.
You can also substitute 1:1 canned pumpkin for the sweet potato. Simply adjust the coconut sugar to ⅓ of a cup.