This cake was inspired by Karythopita - a traditional Greek dessert. Karythopita translates as walnut pie, which is is very misleading as there's no pastry involved. It is actually a rich walnut sheet cake soaked with syrup (usually sugar and honey syrup).
The baking gods must have been smiling on me when I baked this cake because it turned out perfect. The sponge is fluffy, nutty and moist. The yoghurt filling is rich, tangy and not overly sweet. As for the butterscotch sauce... well, words fail me. Lets just say I now want to add it to absolutely everything I bake.
I used 2x15cm/6inch cake tins, but you can use 2x20cm/8inch tins - the layers will simply be a bit thinner. If you wish to make a large celebration cake I would suggest doubling the recipe. Serves 6-8 depending on how generous you are with your slices!