Flourless Chocolate Cake
8 large eggs, cold
1 lb bittersweet or semisweet chocolate chips
1/2 lb unsalted butter (2 sticks), cut in to pieces
1/4 cup espresso (optional)
Confectioner's sugar or cocoa powder for decoration
Adjust oven rack to lower middle position and heat oven to 325 degrees.
Line bottom of 8-inch springform pan with parchment and grease pan
sides. Cover pan underneath and along sides with sheet of heavy-duty
foil and set in large roasting pan. Bring kettle of water to boil.
Beat eggs with hand-held mixer at high speed until volume doubles to
approximately 1 quart, about 5 minutes. Alternately, beat in bowl of
electric mixer fitted with wire whip attachment at medium speed (speed 6
on a KitchenAid) to achieve same result, about 5 minutes.
Meanwhile, melt chocolate and butter (adding coffee or liqueur, if
using) in large heat-proof bowl set over pan of almost simmering water,
until smooth and very warm (about 115 degrees on an instant-read
thermometer), stirring once or twice. (For the microwave, melt chocolate
and butter together at 50 percent power until smooth and warm, 4 to 6
minutes, stirring once or twice.) Fold 1/3 of egg foam into chocolate
mixture using large rubber spatula until only a few streaks of egg are
visible; fold in half of remaining foam, then last of remaining foam,
until mixture is totally homogenous.
Scrape batter into prepared springform pan and smooth surface with
rubber spatula. Set roasting pan on oven rack and pour enough boiling
water to come about halfway up side of springform pan. Bake until cake
has risen slightly, edges are just beginning to set, a thin glazed crust
(like a brownie) has formed on surface, and an instant read thermometer
inserted halfway through center of cake registers 140 degrees, 22 to 25
minutes. Remove cake pan from water bath and set on wire rack; cool to
room temperature. Cover and refrigerate overnight to mellow (can be
covered and refrigerated for up to 4 days).
About 30 minutes before serving, remove springform pan sides, invert
cake on sheet of waxed paper, peel off parchment pan liner, and turn
cake right side up on serving platter. Sieve light sprinkling of
Confectioners’ sugar or unsweetened cocoa powder over cake to decorate,
if desired.