The sponge has a lovely crunchy demerara sugar topping |
I know sometimes it's not convenient to buy buttermilk and a buttermilk substitute can be made by taking 250ml milk (not semi-skimmed) and pouring onto 1 tablespoon of either white wine vinegar or lemon juice and leave to stand at room temperature for 10 minutes.
Recipe is from The Great British Bake Off Everyday cookbook and they recommend serving the sponge with Hot Berry Sauce (recipe in the book). The cake is quite sweet and I think the berry sauce would counteract the sweetness. I served my cake with a dollop of cream.