Joffre Layered Cake

Description
In Romanian: Tort Joffre

Ingredients

 * 7 egg whites
 * 10 oz / 300 g confectioner's sugar

Filling

 * 10 oz / 300 g chocolate
 * ½ cup milk
 * 10 oz / 300 g butter
 * 7 yolks
 * 5 oz / 150 g confectioner's sugar
 * 1 tablespoon rum

Directions

 * 1) Whip the egg whites with the sugar in a bowl placed in a larger one with boiling water.
 * 2) From this mixture, bake 5 sheets in the cake pan which was previously lightly waxed.
 * 3) Spread cream on the cold sheets, place one on top of the other and glaze with the same cream.
 * 4) For the cream, melt the chocolate in milk, let bubble for a minute or two, then refrigerate.
 * 5) In the meantime, beat the butter with the sugar, add the yolks, one by one, then gradually add the melted chocolate, mixing well, and the rum.