1.Firstly, weigh the eggs (in the shell) and make a note of the weight.
2.Weigh out the weight of the eggs in sugar, flour and margarine (if the eggs weigh 200g, you need 200g of sugar, flour and margarine.
3.Beat the margarine and sugar in a large mixing bowl, until the consistency is creamy, the aim at this stage is to incorporate as much air into the mixture as possible.
4.Break the eggs into the margarine and sugar mix, add the flour, baking powder and any flavourings.
5.Mix the ingredients together, trying to incorporate as much air as possible.
Check that the mixture is of dropping consistency, in other words, when you lift and tilt a spoonful of the mixture it should naturally drop back into the bowl and not run or stay on the spoon. Add a little milk or flour if necessary.
6.Divide the mixture evenly between two greased 18cm cake tins, and place in a 180 degrees C oven for 25 to 30 minutes. Do not open the oven until at least 20 minutes have passed (doing so will release the air from the sponge mix). 7.
7.When the sponges are cooked you should be able to lightly press the top with your fingers and it should spring back into place.
8.Remove the sponges from the oven and place on a cooling rack.
9.While the sponges are cooling make the buttercream, by beating together the butter and icing sugar, and any flavourings. Add as much or as little icing sugar as is required to overcome the âÂÂbutteryâÂÂ flavour.