Place 25 g of ginger cake (gingerbread) cut into small pieces in the base of each of the glasses.
Pour 1 tbsp of ginger syrup into each glass.
Put 4 tbsp of rhubarb compote into each glass.
Divide the custard between the four glasses covering the rhubarb.
Whip the cream until it forms soft peaks, and either pipe it on top or spoon it over the custard. Chill in the fridge for at least 3 hours.
Add a few pieces of crystallised ginger to the top of each trifle before serving.
Notes
If you want to add jelly to your trifle, then I suggest that you use raspberry or strawberry jelly. Make up the jelly according to the packet instructions and pour over the ginger cake and rhubarb then leave in the fridge to set before adding the custard and cream.