For the fillings, place the hazelnuts on a baking pan and toast them at 350 degrees for about 15 minutes, or until the skins slip off easily. Pour the hazelnuts onto a towel, cover them with the towel, and rub to loosen the skins. Separate the hazelnuts from the skins, cool, and chop them coarsely. Chop
Whip the chilled chocolate filling by machine until light, about 30 seconds on medium speed. Spread the chocolate filling about 1 inch thick on the slices of pan di spagna lining the bowl, leaving room in the center for the remaining filling. Remove the whipped cream from the refrigerator and rewhip until firm, beating in the remaining rum. Fold in the hazelnuts and reserved chopped chocolate and place the filling in the center of the other filling. Spread the top so it is even, cover with the reserved horizontal layer of pan di spagna, and trim the layer so that it is the same diameter as the inside of the bowl.
Chill the zuccotto in the freezer for 3 or 4 hours to allow the fillings to set. Keep in the refrigerator until serving time. To unmold, invert a platter onto the zuccotto, reinvert, and lift off the bowl. It should lift off easily. If not, wipe the outside of the bowl with a cloth wrung out in very hot water so that the butter between the bowl and the plastic wrap melts. Invert, lift off the bowl, and peel away the plastic wrap. If the outside of the zuccotto is very dry, brush with a little more rum. Dust heavily with the confectioners’ sugar and lightly with the cocoa. To prepare the zuccotto in advance, unmold it on the platter, cover with plastic wrap, and refrigerate until serving time. Dust with the confectioners’ sugar and cocoa immediately before serving.
Confectioners’ sugar and unsweetened cocoa powder for finishing
© 1990 Nick Malgieri. All rights reserved.