1 head green cabbage, finely chopped in a food processor
2 large carrots, finely chopped in a food processor
3/4 cup real mayonnaise
2 tablespoons sour cream
2 tablespoons grated red onion
2 tablespoons sugar, or more to taste
2 tablespoons white vinegar
1 tablespoon dry mustard
2 teaspoons celery salt
salt and freshly ground black pepper

Combine the chopped cabbage and carrots in a large bowl. Whisk together the mayonnaise, sour cream, onion, sugar, vinegar, mustard, celery salt, salt, and pepper in a medium bowl, and then add to the cabbage mixture. Mix well to combine and taste. Adjust seasoning if necessary.