Add the cooked sweet potato, almond milk, melted vegan butter, pure vanilla extract and apple cider vinegar to a food processor, or blender. Process until smooth.
In a large mixing bowl whisk together the all-purpose flour, brown sugar, ground flaxseed, baking powder, salt and cinnamon.
Add the sweet potato mixture and stir until combined.
Spoon the batter onto the waffle iron and cook according to the iron's instructions.Serve with vegan butter, maple syrup and a side of fresh fruit.