Pre-heat the oven to 140C/275F/Gas 1. Grease a 23cm deep cake tin.
Measure all the cake ingredients into a large bowl and mix thoroughly . Beat the mixture for 2-3 minutes until smooth. Spoon into the tin and level the surface.
Bake in a pre-heated over for about 3-3 ½ hours or until a knife inserted in the centre comes out clean. Allow to cool in the tin.
Once removed from the tin this cake can be stored wrapped in grease proof paper and kept in a cool place.