In a large mixing bowl, whisk together flour, sugar, baking powder, and salt until well mixed.

In a separate bowl, combine milk, melted butter, egg, and vanilla extract. Whisk until smooth.

Gently pour the wet mixture into the dry ingredients, stirring lightly until just combined; a few lumps are okay.

Preheat a nonstick skillet over medium heat for about 2 minutes. Lightly grease if desired.

Scoop about ⅓ cup of batter onto the skillet and cook until bubbles form; this takes about 2-3 minutes.

Flip each pancake carefully and cook for an additional 1-2 minutes until golden brown.

Transfer cooked pancakes to a plate, cover with a towel to keep warm, and serve immediately.