Two spring onions, two washed mackerel fillets, 50g/2oz Roccaverano robiola, 1kg/35oz salt, grated orange and lemon peels, one green apple, 300ml/10½ fl. oz. water, 200ml/7 fl. oz. white wine, 200ml/7 fl. oz. white wine vinegar, 90g/3oz sugar, 2 cloves, salt and lemon, 2 laurel leaves, 30ml/1 fl. oz. extra virgin olive oil, 20g/½oz chopped parsley, thyme and chives, salt and pepper. For the apple ice-cream: 2 Granny Smith apples, 100ml/3½ fl. oz. water, salt and 10 drops of lemon.
For the cipollata: mix salt with the citrus fruits peels, marinate the mackerel fillets in this mixture, making sure that they are completely submerged and leave them in the fridge for a couple of hours. Boil onions for 5 minutes in salt water, adding white wine, vinegar, sugar, chives and laurel. Drain the onions off and cut them slightly, put them in a pan with a drop of oil and cook for 5 minutes. Mix the robiola with the pot herbs, set it aside in a freshly place. Wash the fillets, and cut them finely. Cut into julienne strips the washed green apple and stir it into the onions, with this mixture create a hoof 1cm/0.40 inch high in the centre of a plate. Put the robiola cream into a pastry bag and create heaps on the previous mixture. Dress the mackerel with a drizzle of olive oil and garnish with shiso leaves. For the apple ice-cream. Wash and cut into small pieces the apple with its peel, add all the other ingredients and blast-chill it in a Paco Jet backer. Before to serve, pacotize to obtain the perfect frozen to put on the mackerel.