3 tablespoons unsalted butter, plus more for the pan
2 1/2 cups all-purpose flour
1 1/2 teaspoons ground cinnamon
1 1/2 teaspoons ground nutmeg
1 teaspoon baking powder
1 teaspoon baking soda
1/2 teaspoon salt
2 large eggs
2 cups buttermilk
1/2 cup milk
2 tablespoons packed brown sugar
1 cup mashed sweet potato (see Recipe Notes)
Maple syrup, for serving (optional)
Chopped pecans, for serving (optional)
Either in the microwave or on the stovetop, melt the 3 tablespoons of butter, then set aside to cool.
In a medium bowl, whisk together the flour, cinnamon, nutmeg, baking powder, baking soda, and salt.
In a large bowl, whisk together the eggs, buttermilk, milk, and sugar, mixing until completely combined. Stir in the mashed sweet potato. Pour in the melted butter and mix until fully incorporated. Fold in the dry ingredients, mixing until just combined. Don't overmix the batter; it will be lumpy, and that's okay. Let the batter rest for 5 minutes.
Heat a large skillet over medium heat and add a pat of butter — just enough to coat the surface. Once hot, use a 1/4-cup measure to pour batter into the skillet. Cook until the undersides are golden, the edges look to be set, and bubbles form and burst on the surface of the pancake, 2 to 3 minutes. Flip and cook the other side until golden-brown, about another 2 minutes. Repeat with the remaining pancakes.
Serve the pancakes immediately with maple syrup and pecans, or your favorite topping.