Whisk together the flour, baking powder, salt, and sugar in a large bowl until well combined. This creates a fluffy, even dry mixture.
In a separate bowl, beat the egg yolks with the warm milk and melted butter until smooth and slightly frothy.
Gently fold the wet mixture into the dry ingredients, stirring just enough until combined — don’t overmix, as this keeps the pancakes light.
In another clean bowl, beat the egg whites with an electric mixer until stiff peaks form; they should look glossy and stand upright when the beaters are lifted.
Gently fold the whipped egg whites into the batter in three parts, using a spatula and cutting downward motion to keep the batter airy and fluffy.
Heat a non-stick skillet or griddle over medium-low heat; wait until it’s hot enough that a few drops of water sizzle and evaporate quickly.
Spoon or ladle some batter onto the hot surface, forming 4-inch circles, and cook until bubbles form on the surface and the edges look set, about 2-3 minutes.
Carefully flip the pancakes using a spatula, and cook for another 2 minutes until golden brown and cooked through.
Transfer the cooked pancakes to a warm plate; repeat with the remaining batter, adjusting the heat to prevent burning.
Serve the pancakes stacked high, with butter and syrup if desired, enjoying their soft, fluffy texture and golden appearance.
