Carefully remove the waffle and repeat with the remaining batter.
Close the lid and cook according to the manufacturer's instructions, usually 5-7 minutes.
Combine the wet and dry ingredients, stirring until just mixed.
In a large bowl, mix the flour, baking powder, cinnamon, and salt.
In another bowl, whisk together the mashed sweet potatoes, milk, eggs, and melted butter until smooth.
Pour about 1/3 cup of batter into the waffle maker, spreading it evenly.
Preheat the waffle maker.
Serve warm with syrup or toppings of choice.
Spray the waffle maker with cooking spray.