This classic, butter-enriched whisked sponge has many uses. It also freezes well.
MAKES A 20CM SPONGE CAKE
20g softened butter, for greasing
125g plain flour, plus extra for dusting
4 medium eggs, at room temperature
125g caster sugar
30g butter, melted and cooled to tepid
Preheat the oven to 190°C/Gas 5. Brush a 20cm cake tin lightly with the butter and dust with flour.
Put the eggs and sugar into a bowl and whisk together. Continue to whisk for about 12 minutes until the mixture is pale and thickened enough to leave a ribbon trail when you lift the whisk. (You can also do this in an electric mixer.)
Shower in the flour and delicately fold it into the mixture, with a rubber spatula. Add the melted butter and fold in carefully, without overworking the mixture. Pour the mixture into the cake tin.
Bake for 30 minutes or until it is cooked. To test, lightly press the centre of the sponge with your fingertips; there should be a slight resistance. Invert on to a wire rack, giving the sponge a quarter-turn after 10 minutes to prevent it sticking. Leave to cool for 3–4 hours.