In a bowl, whisk together flour, sugar, baking powder, and salt.
In another bowl, beat the milk and egg until frothy. Stir in the melted butter.
Pour the wet ingredients into the dry mix and stir gently until just combined; lumps are fine.
Heat a non-stick skillet over medium heat and lightly grease it.
Pour about 1/4 cup of batter for each pancake onto the skillet. Cook until bubbles form (about 2-3 minutes), then flip and cook until golden brown on both sides.
Serve warm with your favorite toppings.