Grease and flour a cake tin.
Mix the softened butter with the sugar and a pinch of salt.
Whisk the eggs with the milk, then add them to the butter mixture.
Sift the flour, baking powder and starch, then stir into the butter and egg mixture. Add the yoghurt, grated coconut, lemon zest and Amarena Fabbri.
Pour the mixture into the tin and bake at 200°C for 15 minutes. Cut it lengthwise and bake at 180°C for 40-50 minutes.
Leave to cool completely inside the tin, then remove and decorate with icing sugar.