Molten Chocolate Cake

Folding: keeping the air in 34 recipes

• The air was actually built first and it shows: whatever was creamed or whipped has changed colour and grown in volume, pale and light rather than dense.
• The two mixtures were brought closer before being combined: a little of the light one worked into the heavy one first, so the rest is not beaten flat trying to move it.
• Folded and not stirred: a broad implement down through the middle, across the base, up and over, with the bowl turned between strokes.
• Stopped the moment the streaks disappear. It is still visibly aerated and holds its shape briefly when the spoon lifts away.
• Into the tin and into the oven straight away: a batter left standing on the bench gives back the air it was built for.

Where it goes wrong It was stirred until it looked perfectly smooth. Every stroke past the point where the streaks vanish knocks out air that cannot be put back, so the bake comes out dense and short of the tin, and often wet through the middle where there was no structure to hold it.

Chilling to firm: the fridge as binder 48 recipes

• It went cold before it was handled any further, and it went in spread flat and covered rather than as a warm mass that insulates its own centre.
• It is cold through rather than cold at the edge: tested at the middle it is as firm as it is at the rim.
• It holds its shape unsupported; it can be cut, portioned, rolled or lifted without slumping, tearing, or sticking to the hands.
• The fat in it has gone solid: it feels firm and waxy to the fingers rather than greasy and yielding.
• It survives the step it was chilled for, going into heat or a coating or a mould still holding its form rather than collapsing the moment it is touched.

Where it goes wrong It was given twenty minutes instead of the hours it needed, so it is firm at the rim and soft at the core: it slumps out of shape as it is portioned, and everything made from it spreads or breaks apart in the pan.