Ingredients:

  • 4 large eggs, separated
  • 1 cup granulated sugar
  • 1/3 cup unsweetened cocoa powder
  • 1/2 cup all-purpose flour
  • 1/4 teaspoon salt
  • 1/2 teaspoon vanilla extract
  • 1 cup unsalted butter, softened
  • 4 cups powdered sugar
  • 1/2 cup unsweetened cocoa powder
  • 1/4 cup heavy cream
  • 1 teaspoon vanilla extract
  • Powdered sugar for dusting
  • Chocolate shavings or berries for garnish

Instructions:

  1. Preheat the oven to 350°F (175°C). Prepare the jelly roll pan with parchment paper.
  2. In a mixing bowl, whisk egg yolks and sugar until pale and thick.
  3. Gently fold in cocoa powder, flour, and vanilla extract with the egg mixture.
  4. In another bowl, beat egg whites and salt until stiff peaks form, then fold into the chocolate mixture.
  5. Spread the batter evenly in the prepared pan and smooth with an offset spatula.
  6. Bake for 12-15 minutes until the sponge springs back when touched.
  7. While the sponge bakes, prepare a clean kitchen towel dusted with powdered sugar on a flat surface.
  8. Once baked, invert the sponge onto the towel and peel off the parchment paper.
  9. Roll the warm sponge with the towel, letting it cool as it sits.
  10. For the filling, beat the softened butter until creamy, then gradually add powdered sugar, cocoa powder, cream, and vanilla until smooth.
  11. Unroll the sponge gently, spread a layer of chocolate buttercream, and re-roll tightly.
  12. Trim the ends and place the log seam-side down on a serving platter.
  13. Frost the outside of the log with remaining buttercream and use a fork to create a bark-like texture.
  14. Chill in the refrigerator before serving, then decorate with powdered sugar and chocolate shavings.