Chocolate Hazelnut Ganache Cake

Ingredients for the cake:
6 large eggs, separated
pinch of salt
1/2 cup unsalted butter, softened
1 13-ounce jar of Nutella
1 T Cognac
1/2 cup finely ground hazelnuts
4 ounces semisweet chocolate, melted and cooled

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Ingredients for the ganache:
4 ounces whole hazelnuts
1/2 cup heavy cream
1 T Cognac
4 ounces semisweet chocolate

Preparing the cake:
Preheat oven to 350 degrees F. Butter a 9-inch springform pan. In a large bowl (preferably metal), whisk the egg whites and salt until stiff. In another bowl, cream the butter and Nutella, then add the Cognac, egg yolks, and ground hazelnuts. Fold in the melted chocolate.

Add a large scoop of the beaten egg whites to the chocolate batter, and mix gently until well combined. Fold in the remaining whites, one-third at a time, very gently but thoroughly. Pour into springform and bake for 40 minutes. Test for doneness by inserting tester, which should come out mostly clean; lightly pressing finger into top to check for a slight bouncing-back; and observing edges beginning to separate from pan. Let cool completely, in pan, on a rack.

Toast the hazelnuts in a dry skillet, or roast in a hot oven for about 4 minutes, or until they are lightly browned. Let cool completely wrapped in a towel after toasting and rub to remove the skins.

Chop chocolate, and add to saucepan with half and half and Cognac over medium-low heat. Once chocolate is melted and components are combined, whisk until mixture reaches desired thickness, then cool. Remove rim of cake pan and pour cooled ganache over, spreading lightly to create a smooth, shiny surface, and apply hazelnuts all over.