I made this tonight and it was absolutely delicious.  So moist and flavorful.   Here is how I made it...

Buttermilk Roast Chicken

2 cups buttermilk
5 garlic cloves, peeled and smashed
1 tablespoon Kosher salt
1 tablespoon granulated sugar
1 1/2 teaspoons paprika  (Hungarian or smoked)
Lots of freshly ground black pepper
2 1/2 to 3 pounds chicken parts
Drizzle of olive oil
kicher salt and smoked paprika to finish

Whisk buttermilk with garlic, salt, sugar, paprika and lots of freshly ground black pepper in a bowl. Place chicken parts in a gallon-sized freezer bag (or lidded container) and pour buttermilk brine over them, then swish it around so that all parts are covered. Refrigerate for  24 and up to 48 hours.

When ready to roast, preheat oven to 425 degrees. Line a baking sheet (with sides) with foil and put a rack on the baking sheet.  Remove chicken from buttermilk brine, let excess drip off and arrange on rack. Drizzle lightly with olive oil, then sprinkle with additional paprika and salt to taste. Roast for 45-55 minutes (depending on chicken parts), until brown and a deep mahogony color (but not burnt).  Serve and enjoy..