Polskie Nalesniki (Polish Pancakes)

In a spacious mixing bowl, combine the flour, eggs, milk, water, salt, and sugar. Use a hand mixer to blend these ingredients thoroughly until you achieve a smooth, silky batter free of lumps. This ensures your pancakes will be light and tender. Next, gently mix in the melted butter or vegetable oil. This addition enriches the batter and helps prevent sticking during cooking. Alternatively, you may choose to use the butter or oil just to grease your pan before frying each pancake, which also adds a delicious golden crust. Set a non-stick pan over medium heat until it's hot but not smoking. Pour a small ladle of batter into the center of the pan, then swiftly tilt and swirl the pan in a circular motion to spread the batter evenly into a thin layer. Cook the pancake until the edges begin to lift slightly, and the surface loses its wet shine—this is your cue to flip. Carefully turn the pancake over using a spatula and cook for a brief moment on the other side, just until lightly browned. Transfer the cooked pancake to a warm plate. Repeat the process for the remaining batter, adjusting the heat if necessary to prevent burning. Serve your Polish pancakes warm, accompanied by your preferred fillings such as fruit preserves, sweetened cheese, or savory fillings. For best results, keep cooked pancakes covered with a clean towel to retain moisture as you prepare the rest.