This may seem like a surprising combination, but one that works beautifully. Blackcurrants grow in our garden in Sweden and every year my father always makes a tart jam with them for scooping onto ice cream. I will frequently bring a jar or two back to London, sometimes with mixed success. The combination of the journey and improper storage has, on at least two occasions, caused the jam to ferment and the jars to explode, which means a sticky, messy cupboard and a trip to the shops if I want to make this pudding. It’s still worth it, though. If you have fresh blackcurrants to hand, do by all means use them to decorate the pavlovas before serving.