Preheat oven to 200°F.
Whisk together flour, baking soda, salt, egg, and buttermilk until smooth.
Heat a griddle or a large heavy skillet over moderate heat until hot enough to make drops of water scatter over its surface, then brush with butter. Working in batches and using a 1/4-cup measure filled halfway, pour batter onto griddle and cook, turning over once, until golden, about 2 minutes per batch. Transfer to a heatproof plate and keep warm, covered, in oven.
Cooks' note:Batter keeps, chilled and covered, 3 days. Thin as necessary with additional buttermilk or water, 1 tablespoon at a time, before using.
Makes 14 (3-inch) pancakes.
For maple syrup apples
Melt butter in large nonstick skillet over medium-high heat. Add apples and 1 tablespoon maple syrup; sauté until apples are tender, about 5 minutes. Mix in remaining 1/2 cup maple syrup and cinnamon.
Spoon apples over pancakes. Serve, passing additional maple syrup.
Makes 4 servings.