Whisk the eggs, sugar, milk, cream and salt in a bowl over a pan of simmering water until it reaches around 80C. Whisk the mixture constantly, being careful not to scramble it!
Remove the bowl from the heat and add the chocolate (or you can sieve the mixture over a jug of chocolate).
Let it sit for 2 minutes then whisk it or use a hand blender until smooth. Add a pinch of flaky salt to finish.
Cover the surface of the cremeux and chill for 6 hours or overnight, then use! Don’t whisk it, you can use it straight from the fridge.
