01 - In a medium bowl, combine strawberries, blueberries, raspberries, and sugar if using. Gently toss and set aside for 10 minutes to allow the juices to develop.
02 - In a large mixing bowl, whip heavy cream to soft peaks using an electric mixer or whisk. Add mascarpone or cream cheese, granulated sugar, and vanilla extract. Continue whipping until the mixture is smooth, thick, and well blended.
03 - If making vanilla custard from scratch, prepare following your preferred method and allow to cool completely before use.
04 - Arrange half of the cake cubes in the bottom of a trifle bowl or individual serving glasses, creating an even layer.
05 - Spoon half of the sugared berries and their juices evenly over the cake cubes.
06 - Evenly spread half of the vanilla custard or pudding over the berry layer.
07 - Smooth half of the prepared vanilla cream mixture over the custard.
08 - Repeat the process with the remaining cake cubes, berries and juices, custard, and vanilla cream, ensuring distinct layers.
09 - Garnish the top with additional berries and fresh mint leaves as desired.
10 - Refrigerate the assembled trifle for at least 1 hour to allow the flavors to meld before serving.