This is a recipe for a chocolate Genoese sponge.  To make a plain version simply replace the cocoa with the same quantity of flour.

175g whole Egg (roughly 3 and a bit eggs – the bit is important)
90g Caster Sugar
65g Plaig Flour
20g Cocoa Powder
45g Unsalted Butter (room temp)

1. Preheat the (fan) oven to 170°C.
2. Grease a 15cm (6inch) round cake tin with melted butter and line with a double thickness (2 sheets) of baking parchment.
3. Melt the butter so that it is liquid but still has a slightly cloudy appearance and put to one side.
4. Whisk the eggs and sugar together on high speed until the mixture is light and fluffy.
5. Sieve the flour an cocoa powder together and fold into the egg mix.
6. Lastly fold in the butter gently (try hard not to knock out the air you have beaten into the mix).
7. Gently pour the batter into the tin.
8. Bake in the over for 30-40mins or until firm to the touch.
9. Take out the oven and leave to cool in the tin for 10 mins before turning out onto a wire cooling rack.

Posts that have used this recipe (or something similar):

Black Forrest Gateau (BFG) 2
Cake Baking School

Scaling Recipes:

The general rule for up-scaling cake recipes is to increase the ingredient quantities by 1.5 times for the next tin size up.  Below are the ingredient measurements for this Genoese sponge for different cake tin sizes (square and round):

	6inch round 5 inch square	7inch round 6 inch square	8inch round 7 inch square	9inch round 8 inch square
Whole Egg	175g	250g	400g	600g
Caster Sugar	90g	130g	200g	300g
Plain Flour	65g	100g	150g	225g
Cocoa Powder	20g	30g	50g	75g
Unsalted Butter	45g	65g	100g	150g