In a blender or mixing bowl, add the eggs, milk, sparkling water, melted butter, and salt. For sweet crepes, add vanilla extract and sugar.
Blend or whisk the mixture until smooth. Gradually add the flour, ensuring there are no lumps.
Let the batter rest for 30 minutes (optional) to improve texture.
Heat a non-stick pan over medium heat and lightly coat with butter.
Pour about ¼ cup of batter into the pan. Swirl the pan to distribute the batter evenly and create a thin layer.
Cook for 1-2 minutes until the edges lift and the bottom is lightly browned. Flip and cook the other side for an additional 30 seconds.
Repeat with the remaining batter, adding more butter as needed.
Serve warm with your choice of fillings, such as fresh fruit, Nutella, or savory options like cheese and ham.
