Preheat waffle iron.

In a large bowl, whisk together flour, sugar, baking powder, and salt. 

In a medium bowl, mix together milk, butter, eggs, and vanilla. 

Pour the wet mixture into the dry mixture and mix only until combined. 

Grease the waffle iron with cooking spray. Add 1/3 c. batter into the waffle iron and cook until golden brown. 

When you remove the waffle iron, place on a wire rack to keep crisp. Serve with maple syrup or your favorite toppings.