Preheat the oven at 180 C. Line a baking tray with Greaseproof paper.
Cream together the margarine and sugar until very soft and smooth.
Add the sieved flour to the creamed mixture, and using a wooden spoon, combine into a loose crumb.
Beat the eggs, together with the essence in a separate bowl. Then mix into the dry ingredients.
Add in the fruit. Using your hands combine until the mixture comes together into a smooth ball.
Using a tablespoon (or larger if you desire) as a rough measuring guide, shape the mixture into rough balls in your hands.
Bake till firm and golden for 18-20 minutes at 180 C. Cakes will continue to harden into their distinctive “Rock” crumbly texture as they cool.