Prepare the jelly as per packet instructions. Place the berries into a serving dish and pour the prepared jelly over the top. Place in the fridge until firm.

Spread the jam onto the sponge and arrange on top of the jelly.

Whisk the custard powder and half of the milk together to form a paste. Place the remaining ingredients in a pan and heat for 2-3 minutes. Whisk in the custard paste. Cook, stirring constantly, until thick. Remove from the heat, cover and allow to cool. Top the trifle with the cool custard and place in the fridge until ready to serve.