Whisk together flour, sugar, baking powder, and salt in a large bowl.

In a separate bowl, whisk egg, milk, melted butter, and vanilla extract until combined.

Pour wet ingredients into dry, folding gently with a spatula until just combined. Do not overmix; a few lumps are fine.

Let batter rest at room temperature for 10-15 minutes.

Heat a lightly greased non-stick griddle or frying pan over medium-low heat.

Pour 1/4 cup batter per pancake onto the hot griddle. Cook for 2-3 minutes until bubbles form on the surface and edges look set.

Flip and cook for another 1-2 minutes until golden brown and cooked through. Transfer finished pancakes to a baking sheet and keep warm in a 200°F (90°C) oven.

Immediately after cooking, coat each warm pancake generously with the cinnamon sugar mixture, pressing gently to adhere.

Serve warm, stacked, and with your favorite toppings like maple syrup, chocolate sauce, or fresh berries.