Preheat your oven to 350 degrees and grease a 9×13 inch baking pan.
Whisk the cake mix, oil, water and eggs together until smooth. Pour the mixture into your prepared pan and smooth the top. Bake it for 25 to 30 minutes, or until the cake springs back when you press it. Let the cake cool completely.
Meanwhile, whisk together the pudding mix and milk in a bowl until smooth and refrigerate. Use an electric mixer to beat the cream, sugar and vanilla until soft peaks form. Fold a cup of whipped cream into the pudding.
Cut the cake, once it has cooled, into 1 ½ inch cubes. Layer half of your cubes into the bottom of a trifle bowl. Drizzle some fudge sauce over the cake, then top with half of the pudding mixture. Sprinkle half of your raspberries over the mixture, then top with half of your remaining whipped cream.
Repeat the process, ending it with whipped cream. If you would like, sprinkle chocolate shavings on the top for garnish.