Coarsely chop the nuts and roast them in a pan without fat. Take out and let cool down. Wash chicory, dab dry and cut into pieces. Peel oranges so that the white skin is completely removed.
Cut oranges into slices. Mix vinegar, 3 tablespoons of water and oil, season with salt, pepper and 1 pinch of sugar. Mix all salad ingredients, arrange on 4 plates and spread vinaigrette over it. Garnish each plate with 3 slices of ham, sprinkle with walnuts and chives.