Whisk dry ingredients together in a medium-sized mixing bowl. In another bowl, beat together eggs, buttermilk, melted butter, and vanilla. Combine wet and dry ingredients until just smooth.
Brush preheated waffle iron lightly with vegetable oil. For a Belgian-style waffle iron, use about 1/2 cup batter. Cook for 2 to 3 minutes until the iron stops steaming and the waffles are golden. Serve warm with maple syrup.