José Pizarro is a Spanish chef who has worked at some of Spain and London's top restaurants. He owns the tapas and sherry bar, José and restaurant Pizarro, in London, and is the author of Seasonal Spanish Food.
1Preheat the oven to 180°C, fan 160°C, gas 4. Put the chocolate and olive oil into a bowl and set over a pan of simmering water. Stir until completely melted, then set aside. Grease a 22cm springform tin and line the base with nonstick baking paper.
2In a large bowl and using an electric hand whisk (or an electric mixer), whisk together the egg yolks and sugar until the mixture is pale, thick and voluminous, this will take a good five minutes or so. Then gently stir in the melted chocolate mixture.
This light-textured cake is easy to make and always popular, especially with wheat-free friends.
3Next, in a clean bowl and using clean whisks, beat the egg whites until they form stiff peaks. Gently fold the whites into the chocolate mixture. Set the tin on a baking tray and pour the chocolate mixture into it.
4Bake for 30 minutes. Leave the cake to cool completely in the tin.
5To serve, release the cake from the tin and transfer to a serving plate or board. Dust the top with cocoa and serve with berries and ice cream.
This sinks as it cools in the tin – don't panic, that's quite normal.