Combine flour (290 g), sugar (60 g), baking powder (4 tsp), baking soda (1/4 tsp) and salt (1/2 tsp) in a bowl. Make a well and add milk (440 ml), melted cooled butter (60 g), vanilla (2 tsp) and egg (1).
Whisk the wet ingredients, then slowly fold into the dry until smooth. Batter should be thick and creamy — if too thick, fold in extra milk (440 ml) a tablespoon at a time. Rest while pan heats.
Heat a nonstick pan over low-medium heat, grease with a little butter. Pour 60ml batter per pancake, spread into a round. Flip when underside is golden and bubbles appear on top; cook until golden. Repeat with remaining batter.