I love the slaw as is. The chicken needs a little extra as others have said. I add chili powder to the buttermilk (I think season salt would work alright to if you want less heat). I also have thought about adding a few drops of hot sauce to the buttermilk to season up the chicken. Also, I make a Texas sheet cake when I make this dinner since I have spare buttermilk and it makes for a wonderfully special Sunday dinner.
I did not make the broccoli slaw due to lack of interest but the chicken was good. I could get away with using 1/2 to 3/4 cup buttermilk to coat the chicken. The chicken was crunchy and buttery.
The chicken coating was flavorless, and the chicken took a lot longer to get done than the recipe says. The slaw dressing was too sour. A disappointment
The store did not have buttermilk, so I used the suggested yogurt/milk substitution and it worked fine. I don't eat mayo, so I also used yogurt for the dressing. Cooking time was perfect - chicken was right at temperature and was very moist. I would make this again.