Lemon Semifreddo

Line a loaf tin with cling film, leaving it hanging over the sides so you can lift the dessert out later.

Whisk the yolks and sugar constantly in a heatproof bowl over simmering water for about 5-6 minutes, until thick and at 70°C.

Take off the heat, add the grated lemon zest and juice, and keep whisking until the mixture cools to lukewarm.

Whip the cold cream to soft peaks; over-whipped cream turns buttery and makes the texture grainy.

Fold the cream into the lemon mixture in three additions with a spatula, pour into the tin, cover and freeze for at least 6 hours.

Take it out 10 minutes before serving, lift out by the film, turn out and slice with a knife dipped in hot water.