In a bowl, whisk together flour, sugar, baking powder, and salt.
In another bowl, mix milk, egg, melted butter, and vanilla.
Pour the wet ingredients into the dry ingredients.
Stir until just combined; do not overmix.
Heat a non-stick skillet over medium heat.
Lightly grease the skillet with butter or oil.
Pour 1/4 cup of batter for each pancake onto the skillet.
Cook until bubbles form on the surface, about 2-3 minutes.
Flip the pancakes and cook for another 2 minutes until golden.
Serve warm with your favorite toppings.