In a large bowl, whisk together the all-purpose flour, baking powder, salt, and sugar.

In another bowl, mix the milk, egg, melted butter, and optional vanilla extract until well blended.

Pour the wet mixture into the dry ingredients, stirring gently until just combined.

Allow the batter to rest for 5–10 minutes.

Preheat a non-stick skillet over medium heat and lightly grease it with butter or oil.

Pour 1/4 cup of batter for each pancake onto the skillet. Cook until bubbles form on the surface and the edges look set, around 2–3 minutes.

Flip the pancakes carefully and cook for another 1–2 minutes, until they are golden brown.

Serve your fluffy pancakes warm with desired toppings.