Lightly oil a large skillet or griddle. Whisk together the flours, baking powder, salt, cinnamon, nutmeg, and sugar.
Whisk together the apple cider vinegar and 1 1/4 cups of the almond or soy milk. Stir in the vegetable oil and sweet potato puree.
Add the wet ingredients to the dry and mix until they're well combined. If the batter is overly thick, add more almond or soy milk, two tablespoons at a time, until it has the right consistency for pancakes (not runny, but easy to scoop and pour into your skillet).
Allow the batter to rest while you heat the skillet or griddle over medium heat. When the skillet is hot, add the batter in 1/4-cup scoops. Allow the batter to cook until small bubbles are forming on the surface of each pancake and the bottom is firm. Flip the pancakes and allow them to cook on the other side for another 2 minutes, or until both sides are golden and the pancakes are fluffy. Transfer the pancakes to cooling rack or a plate while you finish up the batter.