1. Wash and dry the chicken, cut it in streaks and sprinkle it with salt and pepper.
2. Warm the butter in a frying pan and sauté the chicken for 8 minutes on each side.
3. Add the sherry and let the chicken cool down in the pan. Turn it around many times and allow it to absorb the juices that have formed from the cooking. Meanwhile, prepare the vinaigrette:
Whisk together the oil, vinegar, mustard, chocolate and sour cream. Add salt and Cayenne pepper.
4. Wash the lolo rosso and the lettuce and strain well. Cut in strips.
5. Cut the avocado in half, throw the seed away, remove the skin and cut in strips. Let them sit in the lemon juice.
6. Wash the radishes and cut them into quarters.
7. Lay the lettuce leaves out in a large, shallow plate. Place the avocado strips on top and the chicken strips next to each other.
8. Sprinkle with the vinaigrette. Garnish with cherry tomatoes and radishes and serve.