Place the mixed berries in a bowl and gently stir in honey or simple syrup to enhance their sweetness. Set aside to macerate for about 10 minutes.
Break the ladyfingers or sponge cake into bite-sized pieces, then arrange a layer at the bottom of your serving dish.
Pour a generous layer of chilled custard over the sponge, allowing it to seep into every nook and cranny. Use a spatula to smooth the surface slightly.
Spread a handful of the marinated berries evenly over the custard, distributing bright color and tartness across the layer.
Repeat the layers: add another layer of sponge, followed by custard, then berries, until all ingredients are used, finishing with a layer of berries on top.
Cover the assembled trifle with plastic wrap and refrigerate for at least 2 hours, allowing the flavors to meld and the sponge to soften.
Just before serving, gently dollop whipped cream over the top layer of berries, then garnish with fresh mint leaves for a pop of color and aroma.
Slice and serve the berry trifle with a spoon, enjoying the soft sponge, juicy berries, and creamy custard with each bite.