1Shave the cabbage with a sharp knife or mandoline so that you have thin ribbons. Cut the scallions into small pieces. Toss the cabbage, scallions and cilantro in a large bowl.
2Combine the sour cream, mayonnaise, sugar and the zest of the limes in a medium bowl. Season with the salt and pepper and finish with a squeeze of lime juice. Pour over cabbage mixture and toss to combine.