01 - In a medium mixing bowl, vigorously whisk the cold milk with the instant vanilla pudding mix for 2 minutes. Allow the mixture to stand for 5 minutes until set and thickened.
02 - In a chilled mixing bowl, beat the heavy whipping cream with powdered sugar and vanilla extract using an electric mixer or whisk until stiff peaks form. Set aside.
03 - Arrange half of the cake cubes evenly in the bottom of a large clear trifle bowl or glass serving bowl.
04 - Spread one-third of the prepared vanilla pudding over the cake cubes, followed by one-third of the whipped cream.
05 - Distribute half of the sliced strawberries and half of the fresh blueberries evenly over the cream layer.
06 - Layer the remaining cake cubes, followed by the next one-third of the pudding and cream. Top with all remaining raspberries and the rest of the assorted berries.
07 - Spread the final layer of pudding and cover with the remaining whipped cream.
08 - Decorate the surface with extra berries and an optional sprinkle of white chocolate shavings. Refrigerate for at least 2 hours to allow flavors to meld before serving.