Classic Bûche de Noël
 
Makes 1 bûche de Noël
Ingredients
  • ¼ cup (21 grams) Dutch process cocoa powder, plus more for dusting
  • ¼ cup (60 grams) hot water
  • 3 ounces (86 grams) 60% cacao bittersweet chocolate, melted
  • 5 large eggs (250 grams)
  • ½ cup (100 grams) granulated sugar
  • 2 large egg yolks (37 grams)
  • ¾ cup (94 grams) cake flour
  • ½ teaspoon (1.5 grams) kosher salt
  • 3 tablespoons (42 grams) unsalted butter, melted
  • Cold Brew Simple Syrup (recipe follows)
  • Vanilla Bean Buttercream (recipe follows)
  • Chocolate Buttercream (recipe follows)
  • Meringue Mushrooms (recipe follows)
  • Garnish: ground pistachios, confectioners’ sugar
Instructions
  1. Preheat oven to 350°F (180°C). Spray an 18x13-inch rimmed baking sheet with cooking spray; line pan with parchment paper, and spray pan again.
  2. In a small bowl, whisk together cocoa and ¼ cup (60 grams) hot water until dissolved. Add melted chocolate, and whisk until smooth.
  3. In the bowl of a stand mixer, whisk together eggs, granulated sugar, and egg yolks by hand. Place bowl over a saucepan of simmering water. Cook, whisking occasionally, until an instant-read thermometer registers 110°F (43°F), about 5 minutes. Return bowl to stand mixer fitted with the whisk attachment, and beat at high speed until thick and tripled in volume, about 5 minutes.
  4. In a medium bowl, place about 2 cups egg mixture. Fold in warm chocolate mixture. Set aside.
  5. In a small bowl, sift together flour and salt. Using a large balloon whisk, gently fold flour mixture into remaining egg mixture in two additions just until combined. Fold in chocolate mixture. Fold in warm melted butter in two additions. Using an offset spatula, quickly and gently spread batter evenly in prepared pan.
  6. Bake until cake starts to pull away from sides of pan, 10 to 12 minutes. Loosen cake from sides of pan, if needed. Invert onto a tea towel dusted with cocoa. Gently peel off parchment. Starting with one long side, roll up cake and towel together. Let cool completely on a wire rack.
  7. Carefully unroll cake, and brush with Cold Brew Simple Syrup. Spread with Vanilla Bean Buttercream. Reroll cake without towel, and place, seam side down, on a baking sheet, using towel as a sling. Cover with towel, and refrigerate until firm, about 1 hour.
  8. Trim ends of cake flat. Trim 3 to 4 inches diagonally from one end; set aside. Trim a ¾-inch slice from same end; set aside. Place large cut piece at an angle off side of cake, and attach with Chocolate Buttercream. Place small cut piece, angle cut side up, on top, and attach with Chocolate Buttercream. Spread remaining Chocolate Buttercream on outside of cake. Use an offset spatula to create detailed bark ridges. Decorate with Meringue Mushrooms; garnish with ground pistachios and confectioners’ sugar, if desired.
Recipe by Bake from Scratch at https://www.bakefromscratch.com/classic-buche-de-noel-2/