1.Position oven shelves, preheat oven to hot. Grease 25cm x 30cm swiss roll pan, line base and short sides with baking paper, bringing paper 5cm over edges. Grease the baking paper.
2.Beat the four egg whites in a small bowl with electric mixer until soft peaks form, with motor operating, gradually add combined treacle and golden syrup in a thin stream.
3.Add egg yolk, beat until pale and thick. Transfer mixture to large bowl, using a metal spoon, fold in combined triple-sifted flours and spices, and combined water and soda. Pour mixture into prepared pan, gently spreading mixture evenly into corners.
4.Bake cake in hot oven 220°C (200°C fan forced) for about 15 minutes.
5.Meanwhile, place a piece of baking paper cut slightly larger than the cake on bench, sprinkle evenly with coconut. When cake is cooked, turn immediately onto paper, quickly peeling away the lining paper. Working rapidly, use serrated knife to carefully cut away crisp edges from all sides of cake.
6.Carefully roll cake loosely from one short side by lifting paper and using it to guide roll into shape stand 10 seconds then unroll. Re-roll cake, cool to room temperature.
7.Gently unroll cake, spread with mock cream, carefully re-roll cake.
8.Combine sugar, gelatine, milk and water in small saucepan; stir over low heat, without boiling, until sugar and gelatine dissolve. Cool to room temperature.
9.Beat butter and essence in small bowl with electric mixer until white and fluffy. With motor operating, gradually beat in sugar mixture until fluffy, this will take up to 15 minutes.
10.Mock cream thickens on standing. Use whatever kitchen tool you feel most comfortable with to incorporate the ingredients. Some people prefer to use a large metal spoon, some their hand or a rubber or plastic spatula, it doesn’t matter what you use, it’s how you use it.
11.Mock cream is a smooth mixture suitable for cream buns and other similar cakes but not thick enough to use for piping. It should not be refrigerated because of the butter content, it will become rock hard. Cake can be filled up to 2 hours before required.
While this is easy to make, it may take a bit of experimentation with your oven to determine the best temperature and to perfect the timing two elements that are critical for the success of this sponge cake. Every oven is slightly different to another, be guided by your oven manufacturer’s instructions. As a guide, the second shelf up from the oven floor is usually the best position for the cake pan and the temperature should be 200°C in a fan-forced oven. Gentle folding of the water and flour mixtures through the egg mixture is also important for success heavy handling of the mixture equals a heavy sponge cake. storage Cake is best made on the day it is served. Rolling sponge in baking paper Trimming edges of sponge Spreading sponge with mock cream