Step 1: Prepare the Cake

1. Preheat your oven to 350°F (175°C). Line a 15×10-inch jelly roll pan with parchment paper and lightly grease it.
2. In a large bowl, beat the eggs and sugar on high speed for 3-5 minutes until thick and pale.
3. Add the vegetable oil, vanilla extract, and buttermilk, mixing until combined.
4. Sift together the flour, cocoa powder, baking powder, and salt, then gently fold it into the wet ingredients.
5. Pour the batter into the prepared pan, spreading it evenly. Bake for 10-12 minutes, or until the cake springs back when touched.

Step 2: Roll the Cake

1. Lay a clean kitchen towel on the counter and dust it with powdered sugar.
2. Carefully invert the hot cake onto the towel, peel off the parchment paper, and roll the cake with the towel from the short end. Let it cool completely for about 1 hour.

Step 3: Make the Caramel Buttercream

1. In a bowl, beat the butter until light and fluffy.
2. Add the caramel sauce and powdered sugar, mixing until smooth.
3. Stir in the vanilla extract and add heavy cream if needed for consistency.

Step 4: Fill and Reroll the Cake

1. Gently unroll the cooled cake and spread the caramel buttercream evenly.
2. Roll the cake back up (without the towel) and place it seam-side down on a plate. Chill for 30 minutes to set.

Step 5: Make the Chocolate Ganache

1. Heat the heavy cream in a small saucepan or microwave until steaming (but not boiling).
2. Pour over the chocolate chips and let sit for 2 minutes, then stir until smooth.
3. Add corn syrup and vanilla extract, then let cool slightly.

Step 6: Decorate the Cake

1. Pour or spread the ganache over the cake roll.
2. Sprinkle with toasted pecans and drizzle with extra caramel, if desired.
3. Let the ganache set for at least 30 minutes before slicing.