Macerated berries:

Place the berries, Grand Marnier and sugar in a bowl and mix to combine. Set aside to macerate while you prepare the other elements.

Place the jelly crystals in a mixing bowl and pour over 4 cups of boiling water, mix until all the crystals are dissolved. Pour the jelly mixture into the bottom of a medium-sized trifle dish or glass bowl. Place in the fridge to begin to set. After about an hour, when the jelly has started to set, carefully press the sliced berries into the jelly and up against the edges of the trifle dish or bowl to make a decorative pattern. Return to the fridge until completely set.

Cheat's Chocolate Mousse:

Place the chocolate, butter, marshmallows & ¼ cup cream in a large saucepan over a low heat. Stir regularly until completely melted. Remove from the heat and stir through the Grand Marnier. Leave to cool slightly. Whip the rest of the cream until you have soft peaks, then fold it into the cooled chocolate mixture until completely incorporated. Place in the fridge for about an hour, until beginning to set.

To assemble:

Arrange the lamington cubes in the trifle dish on top of the jelly layer, saving a few for final decoration. Spoon over the macerated berries & juices so they soak into the lamingtons. Layer over the chocolate mousse. At this stage you can place back in the fridge until you’re ready to serve. When ready to serve, top with the whipped cream and decorate with the fresh berries or cherries, extra lamingtons, pieces of chocolate and cubes of strawberry jelly.