Preheat oven to 180 degrees C. Grease one ring tin.
Cream oil, beaten eggs, pumpkin and vanilla together.
Sift the flour, sugar, bicarb soda, ground nutmeg, ground allspice, ground cinnamon, ground cloves and salt together. Add the flour mixture to the pumpkin mixture and mix until just combined. If desired, stir in some chopped nuts. Pour batter into the prepared pan.
Bake for 1 hour or until a toothpick inserted in the middle comes out clean. Let cake cool in pan for 5 minutes then turn out onto a plate and sprinkle with icing sugar.