This is a recipe from my mother’s Finnish friend, Iria. She and my mum say that every Finn has their own recipe for a classic stripey ‘tiger cake’. You can also make this with just vanilla and have a plain sponge cake — good for filling with jam and cream or covering with a chocolate icing — but most people love to see the two different colours in the cake. Children enjoy helping with this — they love licking the beaters and the chocolate and vanilla bowls.