Yule Log Cake
NOTE: The
buttercream and meringue mushrooms require the making of a sugar
syrup heated to 238 degrees, the soft ball stage. Use a candy or
instant-read thermometer for the greatest accuracy. Or, drizzle
some of the syrup into a bowl of cold water and try to shape it
with your fingertips. If syrup forms a soft ball, it has reached
correct temperature. This recipe serves
twelve.
Buttercream
3/4 cup sugar
8 egg yolks
3/4 pound (3 sticks) unsalted butter, at room temperature
1/2 teaspoon vanilla extract
12 ounces bittersweet chocolate, melted
11/2 tablespoons instant espresso powder
2 teaspoons boiling water
Sponge Cake
1 tablespoon unsalted butter, at room temperature
1 cup plain cake flour
1 teaspoon baking powder
1/4 teaspoon salt
3 large eggs
1 cup sugar
1 teaspoon vanilla extract
1 tablespoon brandy or Cognac
Unsweetened cocoa powder
Confectioners' sugar
INSTRUCTIONS:
1. To make buttercream, combine 1/2 cup water and sugar in small, heavy saucepan. Cover and bring to boil over medium-high heat. Boil, swirling pan once or twice, until sugar has dissolved, 1 to 2 minutes. If necessary, wash down any sugar crystals on side of pan with damp pastry brush. Cook, uncovered, until temperature on thermometer registers 238 degrees, about 10 minutes.
2. While syrup is cooking, place egg yolks in large bowl of standing mixer fitted with wire whisk attachment. Beat at medium-high speed until pale yellow and very thick, about 5 minutes. With mixer at medium speed, slowly pour hot syrup into egg yolks, avoiding wire whisk. Continue to beat until mixture cools to room temperature, 5 to 10 minutes. Add butter 1 tablespoon at a time until all butter is thoroughly incorporated. Add vanilla.
3. Transfer one-third of buttercream to another bowl. Stir melted chocolate into first bowl of buttercream. Dissolve instant espresso in boiling water and stir into plain buttercream. Set both buttercreams aside at room temperature for up to 2 hours. (Buttercreams can be covered and refrigerated for 2 days or frozen for 1 week.)
4. Adjust oven rack to middle position and preheat oven to 375 degrees. Grease 16-by-11-inch jelly roll pan with 1 tablespoon butter. Line pan with parchment paper.
5. Sift flour with baking powder and salt; set aside. Place eggs in large bowl of standing mixer fitted with wire whisk attachment. Beat at medium-high speed until pale yellow and very thick, about 5 minutes. Slowly add sugar, then 1/3 cup water and vanilla. Add flour mixture and beat at medium speed until smooth, about 2 minutes. Pour batter into prepared pan, spread with spatula into corners, and rap pan once against counter to settle batter. Bake until cake layer is lightly browned and springs back when touched, 12 to 15 minutes.
6. Run knife along rim of pan to loosen cake. Cover top of cake with piece of parchment paper, then cover completely with large, damp kitchen towel. Place flat side of baking sheet on top of towel. Flip over both pans and lift off baking pan with cake. Carefully peel off top piece of parchment paper.
7. Position cake so that long side faces you. Fold bottom edge of towel and parchment paper over bottom edge of cake (see figure 29). Tightly roll cake (see figure 30) and set aside, seam side down, to cool for 30 minutes. Steady cake on either side with small bowl.
8. If buttercream has been refrigerated, bring to room temperature. Assemble and serve cake as directed in figures 31 through 37.