Separate the eggs. Any yolk in the whites will stop them whipping, so crack each white into a small bowl first before adding it to the main one.

Melt the chocolate gently in a bowl set over barely simmering water, then take it off and let it cool for 5 minutes — hot chocolate will scramble the yolks.

Beat the yolks into the warm chocolate one at a time. It may look thick and grainy; keep going, it comes together.

Whip the whites with the salt to soft peaks — they should flop over at the tip, not stand upright. Over-whipped whites will not fold in.

Stir a third of the whites into the chocolate to loosen it. Then fold in the rest in two additions, cutting down and lifting over, stopping the moment no streaks remain.

Divide into glasses and chill for at least 3 hours.