Preheat the oven to 220°C/430°F/gas 8 and put a baking sheet inside. Brush the insides of four 150ml/5fl oz ramekins with melted butter, sprinkle with caster sugar and tip out the excess.
Make the salted caramel sauce. Place the sugar and 100ml/3½fl oz water in a small pan over low heat, stirring until the sugar has dissolved. Increase the heat and let the mixture bubble until it is a rich caramel colour. Add the cubed butter, stir to melt, then pour in the cream and stir through the salt. Set to one side and gently reheat when ready to serve.
Melt the chocolate with the cream in a heatproof bowl set over a pan of barely simmering water (the bowl should not touch the water).
Remove from the heat and stir through the egg yolks. In a separate, scrupulously clean bowl, whisk the egg whites to form firm peaks.
Add the 35g/1¼oz of sugar a spoonful at a time, whisking between each addition. Stir a spoonful of the whites into the chocolate mixture to loosen up the mix, then carefully fold in the rest.
Divide the soufflé mixture between the ramekins. Run a knife over the top to level, wipe the rims and run a clean fingertip around the edges. Pop onto the preheated baking sheet and turn the temperature down to 200°C/400°F/gas 6. Bake for 10 minutes until risen with a very slight wobble in the centre.
This recipe is extracted from Posh Eggs, out now by Quadrille, RRP £12.99
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