COCOA NIB, CHOCOLATE, AND CITRUS DACQUOISE

Steps:

• For Meringues:
• Preheat oven to 300°F. Line bottoms of two 9-inch-diameter cake pans with 1 1/2-inch-high sides with parchment paper; spray parchment with nonstick spray. Sift powdered sugar and cornstarch into medium bowl; whisk in ground cocoa nibs and 1/2 teaspoon coarse salt. Beat egg whites and cream of tartar in large bowl until thick and foamy. Adding 1 tablespoon sugar at a time, beat until stiff but not dry. Fold in cocoa nib mixture. Divide meringue between prepared pans, spreading evenly.
• Bake meringues 1 hour. Turn off heat. Keeping oven door closed, leave meringues in oven overnight to dry (meringues will deflate slightly).
• Chocolate chiffon cake:
• Preheat oven to 325&Deg;F. Line bottom of 9-inch-diameter cake pan with 2-inch-high sides with parchment paper; spray parchment with nonstick spray. Combine 1/4 cup sugar and next 5 ingredients in medium bowl; whisk to blend.
• Whisk 1/3 cup oil, egg yolks, and 2 tablespoons water in large bowl to blend. Stir in dry ingredients. Beat egg whites in another medium bowl until soft peaks form. Gradually add remaining 1/4 cup sugar, beating until stiff but not dry. Fold whites into yolk mixture. Transfer batter to prepared pan.
• Bake cake until tester inserted into center comes out clean, about 25 minutes. Cool in pan 15 minutes. Turn cake out onto rack; peel off parchment. Cool completely. DO AHEAD: Can be made 1 day ahead. Wrap in foil; store at room temperature.
• For mascarpone whipped cream:
• Combine all ingredients in large bowl. Beat just until mixture holds soft peaks (do not overbeat or mixture will curdle). Cover and chill at least 1 hour and up to 2 hours.
• For glaze:
• Place chocolate in large microwave-safe bowl. Combine heavy whipping cream, 3 tablespoons water, unsweetened cocoa powder, and light corn syrup in heavy medium saucepan. Whisk over medium heat until blended and just beginning to boil. Pour mixture over chopped chocolate; let stand 1 minute, then stir until smooth. Whisk in butter. Let glaze stand until thick enough to spread, 15 to 20 minutes.
• Place 1 meringue on platter, flat side down; spread 1/2 cup glaze over. Refrigerate until chocolate is firmly set, about 30 minutes. Spread half of mascarpone cream (about 1 1/2 cups) over chilled chocolate. Refrigerate 10 minutes. Place cake layer on work surface; spread with 1/2 cup marmalade, then remaining mascarpone cream. Carefully place cake layer atop meringue on platter. Top assembled cake with second meringue, flat side up. Spread 1/3 of glaze over top and sides of cake in thin even layer. Refrigerate until coating sets, about 30 minutes.
• Heat remaining glaze in microwave just until pourable but not hot, 5 to 10 seconds. Carefully pour glaze over cake, spreading to coat evenly. Chill cake until glaze sets, at least 1 hour. DO AHEAD: Cake can be made 3 days ahead. Cover with cake dome and keep refrigerated.
• Cut cold cake into wedges. Serve with blood orange segments.
• Bits of shell-roasted cocoa beans; available at many specialty foods stores and from chocosphere.com.
• ** An Italian cream cheese; sold at many supermarkets and at Italian markets.