Grainy White Chocolate and Mint Mousse

Our answer

Nigella's White Chocolate And Mint Mousse (from Nigella Express) is a fairly simple mousse made with melted white chocolate that is combined with a mixture of whisked cream, egg white and mint extract. It is possible that the egg white and cream were overbeaten, though you would start to see the mixture separating slightly or looking slightly curdled. If you are not sure then it may be better to whisk the egg white to soft/floppy peaks, whisk the cream and mint extract separately to soft peaks and then fold in the egg white. This will give you more control over the texture. Also it may be better if this mixture is not fridge cold when it is added to the melted chocolate.

It is also possible that the chocolate was overheated while it was melting, which would cause it to become grainy. White chocolate is particularly sensitive to temperature, indeed it melts at just above body temperature. If you are not used to melting chocolate then make sure that it is chopped into fairly even-sized chunks and remove the bowl from the pan of water before all of the chocolate has melted and stir until it is smooth and liquid. The unmelted parts usually melt in the residual heat and reduces the risk of the chocolate becoming too hot. Also make sure that no steam or water comes into contact with the chocolate while it melts as this can cause it sieze and become grainy.