Break the biscuits or sponge cake into small crumbs and place them in a bowl. Mash slightly with a fork to create a soft, soakable base.
Spread a layer of berry jam over the crumbled biscuit mixture, allowing it to soak in slightly for added fruity sweetness.
Pour a handful of mixed berries over the biscuit layer, letting their juices seep into the crumbs and creating a juicy, colorful layer.
Whip the heavy cream with a tablespoon of sugar and a splash of lemon juice until soft peaks form, creating a fluffy, airy topping.
Spread or pipe a generous layer of whipped cream over the berries, smoothing it out with a spatula for a soft, creamy layer.
Repeat the layering process—biscuits, jam, berries, and whipped cream—until the bowl is filled, finishing with a final dollop of whipped cream on top.
Garnish with fresh mint leaves or a drizzle of honey if desired, and refrigerate the trifle for at least 2 hours to allow flavors to meld and the layers to soften.