Preheat waffle iron on medium.
Lightly mix dry ingredients (flour, sugar, salt, baking powder, vanilla bean scrapings) in a bowl until evenly distributed. Set aside.
In a different bowl, whisk together wet ingredients (banana, milk, eggs, butter, vanilla extract).
Slowly whisk in the dry ingredients to the wet to avoid clumps.
Ladle the batter into the waffle maker. Amount of batter and cook time vary per machine. Cook waffles until golden brown, generally about 4 1/2 to 6 minutes.