Start by sifting the flour, baking powder, salt, and sugar together in a large bowl. Make a well in the center and pour in the milk, egg, melted butter, and vanilla extract (if using). Use a fork to break up the egg and gently mix the ingredients from the outside in until just combined. Be careful not to overmix—the batter can have lumps.
Next, heat a non-stick griddle or large pan over medium-high heat. If using an electric griddle, set it to 300-350°F. Grease the hot surface with butter or cooking spray.
For each pancake, pour ¼ cup of batter onto the greased pan. Cook for about 2 minutes, until bubbles form on the surface and the edges look set. Flip the pancake and cook for another minute on the other side. Avoid pressing down on the pancakes to keep them light and fluffy.
Transfer the pancakes to a plate and keep warm while you cook the remaining batter.
Once done, stack a few pancakes on a plate and top them with your favorite syrup, butter, fresh fruit, or chocolate chips. Enjoy!