Step 1: In a large bowl, whisk together the instant vanilla pudding mix and cold milk for 2 minutes. Let it sit for 5 minutes to thicken, then gently fold in the whipped heavy cream and vanilla extract to create the custard layer for your boston cream pie trifle.
Step 2: Cut the pound cake into 1-inch cubes. Place half of the cake cubes into the bottom of a glass trifle dish, pressing down slightly to form an even layer.
Step 3: Spread half of the vanilla custard mixture over the cake layer, ensuring it reaches the edges of the dish for a beautiful visual effect.
Step 4: Repeat the layers with the remaining cake cubes and the remaining vanilla custard.
Step 5: To make the ganache, place chocolate chips in a small heat-proof bowl. Heat 1/2 cup of heavy cream in the microwave or on the stove until it begins to simmer. Pour the hot cream over the chocolate chips and let it sit for 3 minutes, then whisk until smooth.
Step 6: Pour the warm chocolate ganache over the top of the boston cream pie trifle and spread evenly. Chill in the refrigerator for at least 4 hours before serving.