In a large mixing bowl, whisk together the all-purpose flour, granulated sugar, baking powder, baking soda, and salt. Make sure there are no lumps.

In a separate medium mixing bowl, whisk together the buttermilk, large egg, melted butter, and vanilla extract until they are well combined.

Pour the wet ingredients into the dry ingredients. Stir with a spatula until just combined. It's okay if there are a few lumps; do not overmix, as this will result in tough pancakes. Overmixing develops the gluten too much.

Let the batter rest at room temperature for 5-10 minutes. This crucial step allows the gluten to relax and the leavening agents to fully activate, leading to exceptionally fluffy pancakes.

Heat a griddle or large non-stick frying pan over medium-low heat. Lightly grease the cooking surface with a pat of butter or a little oil. The griddle is ready when a drop of water sizzles and evaporates quickly.

Pour about 1/4 cup of batter per pancake onto the hot griddle. Cook for 2-3 minutes per side, or until bubbles begin to appear on the surface, the edges look set, and the underside is a beautiful golden brown.

Flip the pancakes carefully and cook for another 1-2 minutes on the second side, or until golden brown and cooked through in the center.

Transfer the cooked pancakes to a plate. Serve immediately with your favorite toppings such as warm maple syrup, fresh berries, whipped cream, or a dusting of powdered sugar. Repeat with the remaining batter, lightly greasing the griddle as needed for each batch.