In a medium-sized mixing bowl, beat together the eggs, buttermilk, melted butter, and vanilla., In a separate bowl whisk together the dry ingredients., Combine the wet and dry ingredients, stirring just until nearly smooth; a few small lumps may remain., Spray your waffle iron with a non-stick cooking spray before preheating it. Cook waffles according to the manufacturer's directions. For an 8" round waffle iron, use about 1/3 cup batter; cook for 2 to 3 minutes, until the iron stops steaming.