Chill the robot-coupe bowl in the freezer for 20 minutes. Which will help prevent the mousse form splitting.  

Blitz the scallops and salt with the egg for 2 minutes, then scrape from sides and slowly add the cream. Ensure you cook a tester before adding further ingredients. 

Add chopped herbs, lemon zest and stir to combine. 

Steam until firm (5-8 minutes)