Semifreddo al Limone

Place the egg yolks, caster sugar, lemon zest and lemon juice in a heatproof bowl set over a pan of gently simmering water. Whisk vigorously and continuously for 8–10 minutes until the mixture is very thick, pale and has tripled in volume — it should hold a thick ribbon for several seconds when the whisk is lifted. This is the zabaglione base. Remove from the heat and continue whisking until the bowl feels cool to the touch. The cooking stabilises the yolks so the semifreddo stays aerated when frozen.

In two separate bowls: whip the cold double cream to soft peaks — it should hold a shape but still be silky and flowing, not stiff. In a separate grease-free bowl, whisk the egg whites with a pinch of salt until they hold firm, glossy peaks. Do not overwhip either — both should be airy and light, not stiff and dry. Keep both chilled until needed.

First fold the whipped whites into the cooled zabaglione in two additions, using a large spatula with a cut-and-lift motion. Then fold in the whipped cream in two additions. Be gentle and decisive — the goal is to retain as much air as possible while achieving a fully uniform, streak-free mixture. The finished base should be light, mousse-like and pale yellow. Pour into a loaf tin lined with two layers of clingfilm, with plenty of overhang on all sides.

Fold the clingfilm over the surface to seal completely. Freeze for a minimum of 4 hours, preferably overnight. To serve: unwrap, invert onto a chilled serving plate and peel off the clingfilm. The semifreddo should hold its shape cleanly and be easy to slice with a warm knife. Decorate the top with candied lemon peel or fresh berries. Slice into 2–3 cm portions and serve immediately — it softens quickly at room temperature.