Melt your Terry's chocolate orange carefully until smooth.
Pour your readymade custard into a bowl, and add in the melted chocolate. Mix together until smooth. If it goes lumpy, heat the custard mix in a pan over a low-medium heat and stir until all smooth and lovely.
Add your double cream to a bowl, add 2tbsp of Cointreau, the icing sugar, and the zest of the orange and whisk to soft peaks.
Slice your chocolate swiss roll into 1-2cm size slices.
Sprinkle over 3-4tbsp of Cointreau, and the juice from the orange.
Start building your trifle - I put the slices of the swiss roll around the edge of the trifle bowl at the bottom, and a few on the bottom as well.
Pour over half of the chocolate orange custard and spread.
Add on the slices of mandarin from the tin, and add on any more swiss roll if you have any. Pour over the rest of the custard.
Spread over the top the whipped orange cream, and decorate with anything you fancy.
I used Terry's chocolate orange slices, grated chocolate, and some extra orange zest along with some festive sprinkles.
Leave it to set a bit in the fridge so the custard isn't as runny. Enjoy!
Notes
This recipe is inspired by Sainsbury's magazine
You can swap the Terry's chocolate orange for normal chocolate if you wish!
The mandarin slices can be slices of orange from the fresh fruit, or you can use the liquid from the mandarin tin in place of the fresh orange juice.
This will last for 3 days once made, but is best eaten fresh.
The cointreau is entirely optional, but can be replaced with more juice from an orange if you want it alcohol free.
Quantities for this recipe are complete estimates as it entirely depends on your trifle bowl!