Cream the butter, caster sugar and lemon rind together until really light. Beat in the eggs, little by little, keeping the mixture stiff. Mix 125 g (4 oz) of the cherries with the flour and baking powder sifted together. Fold the flour and cherries lightly into the cream ingredients with 2 x 15 ml spoons (2 tablespoons) lemon juice. Turn into a greased 1.5 litre (2 1/2 pint) plain ring mould. Bake in a preheated moderate oven (160°C/3 25°F, Gas Mark 3) for about 45 minutes, or until firm to the touch. Turn out onto a wire rack to cool.
Dissolve the sifted icing sugar in 1 to 2 x 15 ml spoons (1 to 2 tablespoons) lemon juice to give a coating consistency. Drizzle over the cake. Decorate with the remaining cherries before the icing sets.