Martha Stewart's Buttermilk Waffles

These were lighgt and fluffy.
2 cups all-purpose flour (spooned and leveled)
2 tablespoons sugar
2 teaspoons baking powder
1 teaspoon baking soda
1/2 teaspoon salt
2 cups low-fat buttermilk
1/2 cup (1 stick) unsalted butter, melted
2 large eggs
Vegetable oil, for waffle iron

Preheat oven to 275 degrees; set a rack on a baking sheet, and place in oven. In a medium bowl, whisk together flour, sugar, baking powder, baking soda, and salt; set aside. In a large bowl, whisk together buttermilk, butter, and eggs; add flour mixture, and mix just until batter is combined.
Heat waffle iron according to manufacturer's instructions; brush with oil. Pour batter onto iron (amount depends on iron size), leaving a 1/2-inch border on all sides (spread batter if necessary). Close iron; cook until waffles are golden brown and crisp, 3 to 5 minutes. Transfer to rack in oven to keep warm; repeat with remaining batter.