Found this on another site.
2 pounds green cabbage
1 medium yellow onion
1/2 cup mayonnaise
1/4 cup mustard
2 teaspoons apple cider vinegar
1 cup sugar
1 teaspoon black pepper
1/2 teaspoon cayenne
Salt and freshly ground black pepper
Cut cabbage in quarters and remove core. Peel carrots and onion and cut into pieces that would fit through the feed tube of a food processor. Fit food processor with the large-holed grater attachment and push cabbage, carrots, and onions through feed tube to grate. In a large bowl, toss vegetables together. Or just buy the package Cole Slaw like I do and I add the onion.
In another medium bowl, prepare the coleslaw dressing by whisking together the mayonnaise, mustard, cider vinegar, sugar, black pepper, and cayenne. Toss dressing with the cabbage mixture, and season with salt and pepper, to taste. Cover with plastic wrap and chill for at least 2 hours before serving.