In a large bowl, whisk together the flour, baking powder, cinnamon, nutmeg, baking soda, and salt.

In a medium bowl or large liquid measuring cup, whisk together the buttermilk and mashed sweet potatoes. Pour the mixture into the bowl with the dry mixture. Then add the oil and egg.

Mix until everything is JUST combined and let it stand while you preheat the griddle or skillet. The batter will be thick.

Heat the griddle to 350° OR heat a non-stick skillet on the stove over medium high heat. Test a small amount of batter first by spooning about a tablespoon onto the griddle. When air pockets start to pop on the surface, or after about 45 seconds, flip. This is just to be sure the heat is right. the first pancake can sometimes be a little wonky with any batch.

Portion the batter out in heaping ¼ cup portions and use the cup to gently push the batter into circles. Wait until air pockets start to pop on the exposed surface OR wait about a minute and flip. Cook for about a minute on the second side.

Work in batches until you've used up all the batter. Serve warm with cinnamon syrup, softened butter and toasted walnuts.