Step 1: Prepare the Cake Batter

• Preheat the oven: Set your oven to 350°F (175°C) and line a 10×15-inch jelly roll pan with parchment paper. Lightly grease the parchment.
• Mix dry ingredients: In a medium bowl, whisk together the flour, cocoa powder, baking powder, baking soda, and salt.
• Beat eggs and sugar: In a large mixing bowl, use an electric mixer to beat the eggs and granulated sugar for 4-5 minutes, or until the mixture becomes thick and pale.
• Add wet ingredients: Gently fold in the vegetable oil, vinegar, vanilla extract, and red food coloring until evenly combined.
• Incorporate dry ingredients and buttermilk: Gradually fold in the dry ingredients and buttermilk alternately, starting and ending with the dry mixture. Be careful not to overmix.

Step 2: Bake and Roll the Cake

• Pour and spread batter: Pour the batter into the prepared jelly roll pan and spread it evenly using an offset spatula. Tap the pan gently on the counter to remove air bubbles.
• Bake: Bake for 10-12 minutes, or until the cake springs back when lightly touched and a toothpick inserted in the center comes out clean.
• Prepare a towel: While the cake bakes, lay a clean kitchen towel on the counter and sprinkle it generously with powdered sugar.
• Roll the cake: Once baked, carefully invert the cake onto the prepared towel. Peel off the parchment paper, then roll the cake (with the towel inside) starting from the short end. Let it cool completely while rolled.

Step 3: Make the Oreo Filling

• Cream butter and cream cheese: In a mixing bowl, beat the softened cream cheese and butter together until smooth and creamy.
• Add powdered sugar and vanilla: Gradually beat in the powdered sugar and vanilla extract until fluffy.
• Fold in Oreos: Gently fold in the crushed Oreo cookies until evenly distributed.

Step 4: Assemble the Cake Roll

• Unroll the cake: Carefully unroll the cooled cake. Spread the Oreo cream filling evenly across the surface, leaving a ½-inch border around the edges.
• Re-roll the cake: Gently re-roll the cake (without the towel), being careful not to squeeze out the filling. Wrap the roll tightly in plastic wrap and refrigerate for at least 1 hour to set.

Step 5: Add the Topping

• Whip the cream: In a cold mixing bowl, whip the heavy cream and powdered sugar until stiff peaks form.
• Decorate the roll: Spread or pipe the whipped cream over the top of the roll. Sprinkle with crushed Oreos and drizzle with melted chocolate for a finishing touch.

Step 6: Serve and Enjoy

• Slice the cake roll with a sharp serrated knife, wiping the blade clean between cuts for neat slices. Serve chilled for the best texture.