Preheat oven to 225°F.
Sift flour into a large bowl.
Add baking powder, cinnamon, nutmeg and salt and whisk until combined.
Combine milk, brown sugar, sweet potato, eggs, vegetable oil and vanilla extract in a large bowl and whisk until well blended.
Add milk mixture to flour mixture and stir until just blended.
Heat a nonstick griddle or skillet over medium-low heat until a few drops of water sizzle on the surface.
Spoon about 1/4 cup of batter per pancake onto skillet.
Cook on first side until tops bubble and sides look dry.
Flip and cook until golden brown, about 2 minutes additional.
Place cooked pancakes on a baking sheet and place into preheated oven to keep warm. Repeat process with remaining batter.
For pecan-honey butter:
Stir together butter, honey and pecans in a medium bowl.
Top pancakes with honey-pecan butter and serve immediately.