Begin with full-fat cream and melt chocolate slowly. Fold them together after cooling the chocolate slightly — this makes the mousse light, not liquid.
Lightly roast your cashews and grind them. Sprinkle over at the time of serving. The crunch on the smooth mousse provides each spoonful with balance.
Fill small glasses or bowls with the mousse before refrigerating. This allows them to set more quickly and provides the finished dish with a clean, café-like appearance.
Add a few drops of coffee or vanilla to the melted chocolate prior to folding. It adds depth to the flavor without dominating the chocolate.
Sprinkle with crushed cashews and perhaps a single chocolate shaving just before serving. It keeps the nuts crunchy and provides the mousse with a fresh finish without added fuss.