Preheat
Preheat waffle iron according to manufacturer’s instructions.
Lightly grease if needed.
Mix Dry Ingredients
In a large bowl, whisk together flour, sugar, baking powder, baking soda, and salt.
Mix Wet Ingredients
In another bowl, whisk buttermilk, eggs, melted butter, and vanilla extract until smooth.
Combine
Pour wet ingredients into dry ingredients.
Stir gently until just combined (small lumps are fine).
Do not overmix.
Cook
Pour about ½–¾ cup batter (or recommended amount for your waffle iron) onto the hot iron.
Close lid and cook 3–5 minutes, until golden brown and crisp.
Remove carefully and repeat with remaining batter.
Keep Crisp
Place finished waffles on a wire rack to prevent sogginess.
Keep warm in a 200°F oven if needed.