01 - Toss sliced strawberries with 1/4 cup granulated sugar and lemon juice in a medium bowl. Let stand at room temperature for 15-20 minutes, stirring occasionally, until strawberries release their juices and become syrupy.
02 - Heat whole milk in a saucepan over medium heat until steaming but not boiling. Meanwhile, whisk egg yolks, sugar, cornstarch, and salt in a heatproof bowl until mixture becomes pale and smooth, approximately 2 minutes.
03 - Slowly pour hot milk into egg mixture while whisking constantly to prevent curdling. Return combined mixture to saucepan and cook over medium heat, stirring continuously with a wooden spoon or heatproof spatula, until custard thickens and bubbles form, 3-5 minutes. Remove from heat immediately and stir in vanilla extract.
04 - Transfer custard to a clean bowl. Press plastic wrap directly onto surface to prevent skin formation. Refrigerate until thoroughly cooled, at least 30 minutes or up to 24 hours before assembling.
05 - Using a chilled bowl and beaters, whip heavy cream on medium-high speed until soft peaks form. Add powdered sugar and vanilla extract, continue beating until stiff peaks form. Refrigerate until assembly.
06 - Arrange half of the pound cake cubes in an even layer across the bottom of a trifle bowl or large glass serving dish. Spoon half of the macerated strawberries and their accumulated juices evenly over the cake layer.
07 - Spread half of the chilled vanilla custard smoothly over the strawberry layer using a spatula, ensuring complete coverage to the edges of the dish.
08 - Repeat layering process with remaining cake cubes, followed by remaining strawberries with juices, then remaining custard. Smooth the top custard layer evenly.
09 - Spread whipped cream over the final custard layer in an even layer. For an elegant presentation, pipe decorative rosettes using a piping bag fitted with a star tip, or create swirls with the back of a spoon.
10 - Refrigerate assembled trifle for at least 30 minutes to allow flavors to meld and layers to set. For optimal texture and flavor development, refrigerate up to 4 hours before serving. Garnish with additional fresh strawberries or mint leaves if desired.