This tangy slaw is quick and simple to prepare and is spectacular in presentation. The savoy cabbage has a delicate taste and texture that pairs well with slightly bitter radicchio.
Put the cabbage, radicchio, onion, and apple in a large bowl and toss together.
In a small bowl, whisk together the vinegar and orange juice. Add the mayonnaise and salt and pepper to taste and whisk until well combined. Pour over the cabbage mixture and toss until well coated.
Taste and adjust the seasonings, if necessary, and serve. The slaw will keep, covered, in the refrigerator for up to a day.