Step 1: In a large bowl, whisk together the flour, granulated sugar, baking powder, baking soda, and salt. Make sure there are no lumps in the dry ingredients.
Step 2: In a separate medium bowl, whisk together the buttermilk, lightly beaten egg, melted butter, and vanilla extract until well combined.
Step 3: Pour the wet ingredients into the dry ingredients. Stir gently with a whisk or spatula until just combined. The batter should still have some lumps; do not overmix, as this will lead to tough pancakes. Let the batter rest for 5-10 minutes.
Step 4: Heat a lightly buttered non-stick griddle or cast-iron pan over medium-low heat. The griddle is ready when a drop of water sizzles and evaporates quickly.
Step 5: Pour ¼ cup of batter for each pancake onto the hot griddle. Cook for 2-3 minutes per side, or until bubbles begin to form on the surface and the edges look set. Flip once and cook for another 1-2 minutes until golden brown and cooked through.
Step 6: Transfer cooked pancakes to a plate and keep warm in a low oven (around 200°F) while you cook the remaining batter. Serve immediately with your favorite toppings.