Tear the leaves from the stems of the cavolo nero and tear into a large bowl
Add the lemon juice, a good pinch of salt and a good slosh of olive oil to the cavolo nero
Massage the mixture into the cavolo nero for a couple of minutes until it starts to relax and soften slightly
In a dry clean frying pan toast the mustard seed and fennel seed for about 1-2 minutes over a gentle heat until they smell fragrant and start to pop
Transfer the toasted seeds to a small bowl to cool
Combine the cooled seeds with the remaining dressing ingredients: dijon mustard, moscatel vinegar and olive oil
Toast the sunflower seeds in the same pan until golden and set aside to cool
Add the fennel, chicory, sunflower seeds and capers to the cavolo nero
Pour in the dressing and toss well
Fork in the tuna and give it all a light toss
