Prepare the crêpe batter by whisking together the eggs, milk, and water in a mixing bowl. Add sugar, salt, and melted butter, then whisk in the flour until smooth, refrigerate for at least 1 hour.

Make the whipped cream filling by beating chilled heavy cream in a mixing bowl until soft peaks form. Gradually incorporate the powdered sugar and vanilla extract, continuing to whip until stiff peaks appear. Refrigerate until ready.

Cook crêpes in a greased skillet over low-medium heat, using about ¼ cup batter for each crêpe, flipping when edges lift. Cook each side until set but not browned. Stack and keep warm.

Assemble the pancakes by placing a cooked crêpe smooth side down, adding whipped cream and mango slices in the center. Fold from sides to center, repeating with remaining crêpes.

Serve immediately, optionally dusting with powdered sugar or garnishing with edible flowers for presentation. Best enjoyed chilled.