In a large bowl, whisk together the flour, baking powder, salt, and sugar until well combined.
In a separate bowl, whisk the milk, beaten egg, melted butter, and vanilla extract until smooth.
Pour the wet ingredients into the dry ingredients and stir gently until just combined; a few small lumps are okay. Do not overmix.
Heat a nonstick skillet or griddle over medium heat and lightly grease with butter or oil. Pour 1/4 cup batter for each pancake onto the hot surface.
Cook until bubbles form on the surface and the edges look set, about 2 to 3 minutes. Flip and cook the other side until golden brown, about 1 to 2 minutes more.
Serve warm with butter, maple syrup, or your favorite toppings.
Notes
For extra fluffiness, let the batter rest for 5 minutes before cooking. You can fold in fresh berries or chocolate chips if desired.