Preheat a waffle iron
In a bowl, mix flour, sugar, baking powder, and salt
In another bowl, whisk eggs, milk, melted butter, and vanilla
Combine the wet and dry ingredients until just mixed
Lightly grease the waffle iron if needed
Pour batter into the waffle iron
Close the lid and cook until golden brown and crisp
Remove the waffle carefully
Repeat with the remaining batter
Serve warm with desired toppings