01 -  In a large bowl, vigorously whisk together the flour, granulated sugar, brown sugar, baking powder, baking soda, cinnamon, nutmeg, and salt until well combined. 
 02 -  In a separate bowl, mix the mashed sweet potato, eggs, milk, vanilla, and melted butter. Whisk until the mixture is smooth and homogeneous. 
 03 -  Add the wet ingredients to the dry ingredients. Stir gently with a spatula or whisk until just incorporated; avoid overmixing as some lumps are preferred for best texture. 
 04 -  Heat a nonstick skillet or griddle over medium heat and lightly brush the surface with melted butter. 
 05 -  Pour approximately 1/4 cup of batter for each pancake onto the skillet. Allow to cook until small bubbles appear on the surface and the edges begin to set, about 2 to 3 minutes. 
 06 -  Turn each pancake and continue cooking for an additional 1 to 2 minutes, until golden brown and thoroughly cooked. 
 07 -  Combine the granulated sugar and ground cinnamon in a small bowl to prepare the cinnamon sugar topping. 
 08 -  While pancakes remain hot, sprinkle each with the cinnamon sugar topping and serve immediately.