Prepare the pudding: In a mixing bowl, whisk together the pudding mix and cold milk for 2 minutes until thickened. Set aside.
Make the whipped cream: In a chilled bowl, beat the heavy whipping cream, powdered sugar, and vanilla extract with a hand mixer until soft peaks form.
Combine pudding and whipped cream: Gently fold half of the whipped cream into the pudding mixture to create a light, mousse-like filling. Set the rest of the whipped cream aside for topping.
Layer the trifle: In your trifle bowl, start with a layer of cubed cake. Then add a layer of the pudding-cream mixture, followed by a mix of berries.
Repeat the layers: Continue layering – cake, pudding, berries – until you reach the top of the bowl.
Top it off: Finish with the remaining whipped cream and a handful of fresh berries.
Chill before serving: Refrigerate for at least 2 hours or overnight to allow flavors to blend and layers to set.
Garnish: Add fresh mint leaves just before serving, if desired.