Stir all dry ingredients together to combine. In a separate bowl, whisk buttermilk, egg, maple syrup and melted butter. Pour buttermilk mixture into dry ingredients and stir just until blended (a few lumps are OK).
Heat a griddle over moderate heat and grease lightly. Drop spoonfuls about 1/4 cup in volume onto griddle and cook until surface of pancake dulls and bottom is golden brown, about 3 minutes. Flip pancakes and cook until other sides browns, about 2 minutes and remove to a plate. Keep pancakes warm while cooking remaining batter and serve with warm maple syrup.