The Top Secret Recipes website has a recipe for a replica of KFC coleslaw. It is originally from Todd Wilbur's "Top Secret Recipes" book series.
The recipe calls for 1 head of cabbage, 1 medium carrot, 2 tablespoons minced onions, 1/2 cup mayonnaise and 1/3 cup granulated sugar. Also gather 1/4 cup milk, 1/4 cup buttermilk, 2 1/2 tablespoons of lemon juice, 1 1/2 tablespoons white vinegar, 1/2 teaspoon salt and 1/8 teaspoon pepper.
Chop the carrots and cabbage into fine pieces, about the size of rice grains. Beat the mayonnaise, milk, buttermilk, sugar, vinegar, lemon juice, salt and pepper in a large bowl. Next, add the cabbage, carrot and onion pieces and mix fully. Cover the coleslaw and place in the fridge for two hours to allow the flavors to develop before serving. This recipe makes between 10 to 12 servings.
The Top Secret Recipes website has an alternate recipe for a healthier version of KFC coleslaw. This recipe is almost identical to the regular recipe, except it calls for light mayonnaise, low-fat milk and reduced-fat buttermilk. It uses 2 tablespoons plus 1 teaspoon instead of 1/3 cup sugar, and substitutes 1/2 tablespoon of white vinegar and 1 teaspoon apple cider vinegar for the original's lemon juice.