Preheat oven to 175°C (350°F). Line a 25 x 38 cm jelly roll pan with parchment paper.

In a large mixing bowl, combine the chocolate cake mix, eggs, vegetable oil, water, and vanilla extract. Mix until the batter is smooth.

Pour the batter into the prepared pan and smooth the surface.

Bake in the preheated oven for 12–15 minutes, or until a toothpick inserted in the center comes out clean.

Dust a clean kitchen towel with powdered sugar.

Once baked, carefully invert the hot cake onto the sugared towel and peel away the parchment paper.

While still warm, roll the cake into the towel from one short edge and allow it to cool completely.

In a mixing bowl, beat the softened cream cheese and unsalted butter until smooth.

Gradually add powdered sugar and vanilla extract, mixing until light and creamy.

Fold in the crushed Oreo cookies.

Gently unroll the cooled cake and spread the Oreo cream filling evenly across the surface.

Roll the cake back up tightly and wrap it in cling film.

Refrigerate for at least 60 minutes.

Unwrap the roll and place it on a serving platter. Drizzle with melted white chocolate, sprinkle with crushed Oreo cookies, and top with whole Oreos.

Slice into portions and serve.