In a large mixing bowl, whisk together flour, baking powder, baking soda, salt, and sugar.
In a separate bowl, beat the eggs, then add buttermilk, melted butter, and vanilla extract.
Combine the wet and dry ingredients, mixing gently until just incorporated—do not overmix.
Let the batter rest for 5 minutes while you heat a skillet or griddle over medium heat.
Lightly grease the skillet with butter, then pour 1/4 cup of batter for each pancake.
Cook until bubbles form and the edges look set, then flip and cook until golden brown.
Serve hot with more butter and a generous drizzle of maple syrup.