6 tablespoons unsalted butter, plus more or greasing the pan
1 1/4 cups granulated sugar
6 large eggs, separated
5 tablespoons instant espresso
6 tablespoons Dutch-processed cocoa powder (recommended: Droste)
6 tablespoons dark rum or Marsala
1 1/2 cups ground, toasted, blanched almonds
All-purpose flour, for coating the pan
Confectioners' sugar, for dusting

cooking and preparation recipeRecipe:

Melt the butter in a glass bowl over simmering water. Once the butter melts, whisk (beat lightly with a whisking utensil or a fork over the top of the mix or batter) in the sugar and the egg yolks, and cook for 5 minutes, stirring constantly so that the eggs become ribbon-like and light in color (don't scramble.) whisk (beat lightly with a whisking utensil or a fork over the top of the mix or batter) in the coffee, cocoa powder, rum and almonds, and continue cooking, stirring constantly, until the mixture becomes smooth and creamy.

Transfer the cake mixture to a mixing bowl and set aside.

Preheat the oven (don't spill oil in it, or it may smoke up) to 375 degrees F.

butter (comes in salted and unsalted types) and flour a 9-inch round cake pan.
In a clean, separate mixing bowl, beat the egg whites until the just begin to stiffen and hold soft peaks. Be sure to stop before they form hard peaks. Gently fold the whites into the chocolate mixture. Pour the batter into the prepared pan and bake until firm and beginning to separate from the sides, about 30 minutes. Remove from the oven and allow to cool 30 minutes more. Flip cake over, dust with confectioners' sugar and cut into wedges before serving.