Preheat your waffle iron according to the manufacturer's instructions. Lightly grease with nonstick spray.
In a medium-sized mixing bowl, whisk together the flour, sugar, baking powder, baking soda, and salt until well combined.
In a separate small mixing bowl, whisk together the buttermilk, egg, melted butter, and vanilla extract until well combined.
Add the wet mixture to the dry mixture and stir until just combined. Be careful not to overmix the batter, as this can make the waffles tough.
Using a ladle or measuring cup, pour the batter onto the center of the hot waffle iron, spreading it out slightly with a spoon or spatula.
Close the waffle iron and cook the waffle for 3-5 minutes, or until it is golden brown and crispy on the outside and cooked through on the inside.
Use a fork or tongs to remove the waffle from the iron and transfer it to a plate. Repeat with the remaining batter, making sure to grease the waffle iron as needed to prevent sticking.
Top the waffles with sifted powdered sugar, butter, and syrup. Serve with milk.