In a large mixing bowl, whisk together flour, sugar, baking powder, baking soda, and salt on cutting board.
In another mixing bowl, whisk together buttermilk, eggs, melted butter, and vanilla extract until well combined.
Pour wet ingredients into dry ingredients. Gently fold with a wooden spoon just until combined - batter should be lumpy with streaks of flour visible. Do not overmix or pancakes will be tough. Let batter rest for 5 minutes.
Heat a grill or cast iron skillet over medium heat. Lightly grease with butter using a paper towel.
Pour 1/4 cup batter onto hot griddle for each pancake. Cook for 2-3 minutes until bubbles form on surface and edges look set.
Flip pancakes using a spatula and cook another 1-2 minutes until golden brown and cooked through. Adjust heat if browning too quickly.
Transfer cooked pancakes to a plate and keep warm in a 200°F oven while cooking remaining batches.
Serve immediately stacked high with butter, warm maple syrup, and your favorite toppings like fresh berries, whipped cream, or powdered sugar.