01 - In a medium mixing bowl, whisk cold milk with instant vanilla pudding mix for two minutes until smooth. Allow to stand for five minutes until thickened.
02 - Using a chilled bowl, beat heavy whipping cream with powdered sugar and vanilla extract until stiff peaks form. Set aside.
03 - Arrange half of the pound cake cubes evenly at the base of a large clear trifle bowl or glass serving dish.
04 - Spread one-third of the vanilla pudding over the cake layer, followed by one-third of the whipped cream.
05 - Evenly distribute half of the sliced strawberries and half of the blueberries over the cream layer.
06 - Repeat the process with remaining cake cubes, another third of the pudding, and another third of the whipped cream. Add remaining raspberries, strawberries, and blueberries in an even layer.
07 - Finish with the remaining vanilla pudding and whipped cream, spreading smoothly over the berries.
08 - Garnish the top with additional fresh berries and, if desired, sprinkle with white chocolate shavings. Refrigerate for at least two hours before serving to allow flavors to meld.