Preheat the oven to 120 °C. Score the skin of the duck in a square and fry the duck breasts in a pan on the skin side until crispy, turn briefly and then place in an oven dish. Pour white wine and soy sauce over the drippings, add sugar and bring to the boil. Add the rosemary and leave to infuse for 5 minutes. Pour the stock over the duck breasts and cook in the oven for 60 minutes until pink.
Fry the almond shells in sunflower oil, place on kitchen paper to drain and salt in a bowl.
Peel the kohlrabi, cut into cubes and place in a stand mixer with all the ingredients, mix to a fine sauce. Pour the sauce into an iSi bottle, fill with an iSi capsule. Shake well and refrigerate.
Wash the lettuce, spin dry and set aside.
Clean the fennel and fry briefly in a pan with a little sesame oil, pour in the vegetable stock. Add cinnamon and rosemary and simmer for 5 minutes. Lightly salt and add olive oil.
Cut shiitake into strips, halve garlic clove and fry everything together in a little peanut oil briefly and very hot. Add some salt and pepper.
To serve, add the kohlrabi foam and sprinkle the dish with almond chips and chilli threads.