Melt chocolate in a heatproof bowl over a saucepan of simmering water and set aside. Bring cream to the boil in a saucepan over medium-high heat, add to chocolate, stir until smooth and set aside.
Whisk yolks and 40ml hot water in a heatproof bowl over a saucepan of simmering water until pale and frothy (2-3 minutes). Transfer to an electric mixer, fold in chocolate mixture and whisk until cooled to room temperature (2-3 minutes). Spoon into a 7cm x 28cm cake tin lined with baking paper (see note), smooth top, scatter with pretzels and refrigerate to chill (overnight).
Cut into fingers with a hot wet knife, scatter with sea salt flakes and serve.
Note If you don’t have a tin of this size, use a 15cm square cake tin instead.
This recipe is from the September 2012 issue of Australian Gourmet Traveller.