How to Make It
In a small saucepan, melt the 6 tablespoons of butter and cook over moderately low heat until the foam rises to the surface and the splattering stops, about 3 minutes. Remove the saucepan from the heat and spoon off the foam. Strain the butter through a cheesecloth-lined sieve into a small bowl; you should have about 4 tablespoons of clarified butter.
In a medium bowl, whisk the flour with the salt. In another medium bowl, beat the eggs, then whisk in the milk, water and the 2 tablespoons of melted butter. Sift the flour mixture over the egg mixture and whisk just to blend the batter; it's okay if there are some lumps.
Heat a crêpe pan or 8-inch nonstick skillet. Add 1/2 tablespoon of the clarified butter and swirl it in the pan. Ladle 1/4 cup of batter into the pan, swirling to spread it in a thin, even 6-inch round. Cook the crêpe over moderate heat until lightly golden on the bottom, about 2 minutes. Flip the crêpe and cook until golden, 1 to 2 minutes longer. Turn the crêpe out onto a plate. Repeat with the remaining clarified butter and batter to make 8 crêpes, stacking them on the plate as you go.
Spread a tablespoon of dulce de leche onto each crêpe and fold it in half. Place 2 folded crêpes on each plate. Top with whipped cream and serve.