01 - Preheat oven to 350°F (175°C). Line a 15×10-inch jelly roll pan with parchment paper and lightly grease the surface.
02 - In a medium bowl, sift together the all-purpose flour, unsweetened cocoa powder, baking powder, and salt until evenly blended.
03 - In a large bowl, beat the eggs and granulated sugar with an electric mixer on high speed for 5 minutes until the mixture is thick, pale, and forms ribbons when lifted.
04 - Fold in the vanilla extract. Gradually add the sifted dry ingredients, alternating with the milk, folding gently until just combined. Do not overmix.
05 - Spread the batter evenly across the prepared jelly roll pan. Bake for 10–12 minutes, or until the cake springs back lightly when touched in the center.
06 - While the cake bakes, lay a clean kitchen towel flat and dust generously with powdered sugar. Immediately upon removing the cake from the oven, invert it onto the towel. Peel off the parchment paper. Starting from a short end, tightly roll the cake and towel together. Cool completely on a wire rack, about 45 minutes.
07 - Gently unroll the cooled cake. Spread the creamy caramel sauce evenly over the entire surface. Sprinkle the toasted chopped pecans uniformly across the caramel layer.
08 - Carefully re-roll the cake, this time without the towel, keeping it snug but gentle to avoid cracking. Place seam-side down on a serving platter.
09 - Heat the heavy cream and unsalted butter in a small saucepan until just simmering. Pour the hot mixture over the chopped semi-sweet chocolate in a heatproof bowl. Let sit for 2 minutes, then whisk until completely smooth. Allow to cool slightly until it reaches a pourable consistency.
10 - Pour the ganache over the rolled cake, spreading evenly across the top and allowing it to drip down the sides. Garnish with extra chopped pecans, caramel drizzle, and chocolate shavings. Chill for 30 minutes before slicing for clean, neat pieces. Serve at room temperature.