Thinly slice or shred cabbage; place in an 8-qt. Dutch oven. Add 2 tablespoons vinegar. Cover and cook over medium heat for 8-10 minutes or until cabbage is crisp-tender, stirring occasionally. Add onion, apples, sugar, mustard and remaining vinegar. Cook, uncovered, for 2-3 minutes.
Place mixture in a large bowl; cover and refrigerate for 1 hour or until completely cool.
Add remaining ingredients; toss to coat. Cover and refrigerate at least 6 hours.