Banana cake is one of those dishes that is incredibly delicious but somewhat overdone. With this recipe you can achieve the same tasty fruit flavours but with a bit of a twist. Adding in some Greek-style yoghurt works so well for this recipe you’ll wonder why you’ve never tried it before. The walnuts on top are optional, but not only do they make the cake look even more pleasing to the eye but they also give it that bit of a crunch!