Preheat oven to moderate 180oC.
Brush a deep, 20 cm baba tin with melted butter or oil.
Using electric beaters, beat butter
and sugar in small mixing bowl until light and creamy.
Add the eggs gradually, beating
the mixture thoroughly after each addition. Add the essence, beat until combined.
Transfer the mixture to a large mixing
bowl. Add zucchini and raisins.
Using a metal spoon, fold in the sifted flour.
Stir until just combined and the
mixture is almost smooth.
Spoon evenly into prepared tin;
smooth surface. Bake for 35 to 40 minutes or until skewer comes out clean when
inserted in centre of cake.
Leave cake in tin 10 minutes before turning
onto wire rack to cool.
To make Vanilla Butter Cream -
Combine sugar and water in small pan. Stir constantly over low heat
until the mixture boils and sugar has dissolved. Reduce heat, simmer
without stirring, uncovered, 5 minutes. Remove from heat, cool.
Using electric beaters, beat butter
and essence in small mixing bowl until light and creamy.
Pour syrup onto creamed mixture,
beating until all has been added and mixture is smooth and fluffy.