Preheat oven to 180ºC and line a 20cm square baking tin with paper that comes up over the sides for easy removal.
Place nuts, sugars, salt, and zest into Thermomix bowl and mill 10 sec/speed 10.
Add remaining ingredients except chocolate and blend 10 sec/speed 5-6.
Press into prepared tin and bake 20-25 minutes until golden and fragrant. Reduce oven temperature to 160ºC and bake further 5 minutes.
Flick with melted chocolate and allow to set.
Cut and serve.