Mix vinegar, salt, pepper and mustard and fold in 4 tablespoons of oil. Peel and chop the shallot. Clean, wash and pluck the radicchio. Mix both with the vinaigrette.
Cut the avocados in half lengthwise, remove the stone. Remove the whole flesh from the skin and sprinkle with lemon juice. Season inside with salt and pepper. Fill the avocado halves with cream cheese, then cut in half lengthwise.
Heat 2 tablespoons of oil in a frying pan. Fry the avocado quarters for about 1 minute on each cut surface. Serve everything.