Prepare the Batter: In a large mixing bowl, whisk together the all-purpose flour, sugar, baking powder, salt, and ground cinnamon for about 2 minutes.

Mix Wet and Dry Ingredients: In a separate bowl, whisk the egg, milk, melted butter, and vanilla extract. Pour into dry ingredients and stir gently until just combined.

Cook the Pancakes: Heat a non-stick skillet over medium heat for 5 minutes. Pour 1/4 cup of batter onto the skillet. Cook until bubbles form, about 2-3 minutes; flip and cook until golden brown, 1-2 minutes more.

Cinnamon Sugar Coating: Remove pancakes from skillet, dip in melted butter, then roll in cinnamon sugar mixture while warm.

Prepare the Vanilla Sauce: Whisk powdered sugar and milk in a small bowl until smooth and drizzlable.

Serve: Stack pancakes on a plate, drizzle with vanilla sauce, and enjoy warm.