In a large bowl, combine flour, baking powder, salt, pumpkin pie spice, and brown sugar. Whisk together until well combined.
Crack you eggs and divide into two bowls. Egg yolks in one bowl, egg whites in the second bowl.
Whisk the egg yolks until smooth. Add the pumpkin puree, maple syrup, vanilla, milk and melted butter to the egg yolks. Whisk until smooth.
Next, whisk your egg whites until frothy and at least double in size.
Add the egg yolk mixture to the dry ingredients and fold together until well incorporated. Then gently fold in your egg whites taking care not to deflate all the bubbles you made.
Set your bowl aside to rest while you preheat your waffle iron.
Once your waffle iron is ready, add 1 tablespoon of chopped pecans to each waffle section. Then add ½ cup of waffle batter on top of the pecans. Cook according to your waffle maker's instructions. (mine cooks about 6 minutes per batch)
Serve immediately or store according to directions in notes.
Notes
To store leftover waffles: Wrap each cooled waffle in a paper towel. Stack together and store in a ziploc bag or airtight container. Then keep in the refrigerator if you will consume within 3-4 days. Otherwise store in the freezer. Reheat in a toaster as you would store bought waffles.