01 - Preheat oven to 350°F. Line a 10x15 inch jelly roll pan with parchment paper and lightly grease it.
02 - In a mixing bowl, beat eggs with sugar and vanilla extract for 5 minutes, or until pale and thick.
03 - Sift together flour, cocoa powder, baking powder, and salt. Gently fold into the egg mixture until just combined.
04 - Pour batter into the prepared pan and spread evenly. Bake for 10–12 minutes, until the cake springs back when touched.
05 - While still hot, turn the cake onto a clean kitchen towel dusted with powdered sugar. Peel off parchment paper. Starting at the short end, roll the cake and towel together into a log. Let cool completely in this shape.
06 - Once cool, unroll the cake. Spread caramel sauce evenly over the surface, reserving 2 tbsp for drizzling. Sprinkle chopped toasted pecans over the caramel layer.
07 - Carefully re-roll the cake without the towel. Place seam-side down on a serving platter.
08 - Pour hot heavy cream over chopped semi-sweet chocolate in a heatproof bowl. Let sit for 2 minutes, then stir until glossy and smooth. Let thicken slightly.
09 - Pour ganache over the cake roll, letting it drip down the sides. Drizzle with reserved caramel sauce and garnish with pecan halves.
10 - Chill for 20 minutes before slicing for clean portions. Serve at room temperature.