Preheat oven to 350 degrees and line the bottom of a 10x15x1" rimmed sheet pan with parchment paper. Do not grease the pan.

Whisk the dry cake mix with the cocoa powder until well combined. Prepare cake mix according to package directions. Pour into prepared pan and bake for 20 minutes, until the edges start to crack. The cake will rise up in the pan, but should not flow over.

Loosen cake from the edges of the pan while it's still warm. it's can be a little sticky, like angel food cake, but it will come away easily.

Spread out a clean lint free kitchen towel and sprinkle ¼ cup powdered sugar evenly all over the kitchen towel. Flip the warm cake out onto the sugar dusted kitchen towel.

Peel the parchment paper off the back side of the cake.

Start rolling the cake up with the kitchen towel, starting at the short end of the cake, WITH the towel rolling with the cake inside. Let the cake cool completely at room temperature for a couple hours or pop it freezer up to 20 minutes if in a hurry. It’s important to let the cake cool completely before adding the cake filling.

In a large bowl, beat the cream cheese with an electric mixer until smooth. Add the 3/4 cup powdered sugar, vanilla and cream and beat on low until combined, then again on high for a few minutes until the mixture is fluffy and stiff peaks form.

Gently unroll the cooled cake (leave it laying on the towel, if you’d like) and spread half of the filling over the top of the cake. Then add a few raspberries onto the cream filling to be rolled up with the cake. Carefully roll the cake back up (without the towel). Place the cake roll on a serving plate. Spread the top with the remaining creamy filling and top with a few more raspberries and a dusting of powdered sugar. Serve right away or you can keep it chilled in the fridge for a few hours before serving.