Flourless Orange-Chocolate Cake
Based on a recipe of Alice Medrich's. The cake can be made ahead and refrigerated overnight (up to 4 days). It must be at room temperature for serving and decorating. Favorite chocolates include Scharffen Berger, Ghirardelli, and Callebaut.
8 eggs, chilled
16 oz (1 pound) semi-sweet or bittersweet chocolate, chopped coarsely
1/2 pound unsalted butter (2 sticks)
pinch fine sea salt
1/4 cup triple sec
zest of one navel orange
1. 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 aluminum foil and set in large roasting pan. Bring kettle of water to boil.
2. Beat eggs until tripled in volume, about 2 quarts. If using hand-held mixer, mix on high speed for about 20 minutes. If using a standing electric mixer, use wire whip attachment at medium speed to achieve same result.
3. Meanwhile, melt chocolate and butter with salt, liqueur, and orange zest in large heatproof bowl set over pan of almost simmering water, stirring until smooth and very warm (115 degrees). (For microwave, melt chocolate and butter at 50% power until smooth and warm, about 6 minutes.) Pour melted chocolate mixture through fine meshed sieve into large mixing bowl. Fold 1/3 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 homogeneous.
4. Scrape batter into prepared springform pan and smooth surface with 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 (it will continue to cook when removed from oven). Remove cake pan from water bath and set on wire rack; cool to room temperature. Optionally, cover and chill.
5. 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. When cake is at room temperature, sieve light sprinkling of Confectioner's sugar or unsweetened cocoa powder over cake to decorate, perhaps through a paper doily.
This cake does well with a sauce. Try a raspberry sauce (frozen raspberries, thawed and sieved, with a few drops of lemon juice and sugar to taste), an orange sauce (follow instructions for lemon curd substituting orange ingredients), or, daringly, a warm orange-caramel sauce.