Nigella Express: Buttermilk Roast Chicken

12 chicken drumsticks (approximately 3 pounds total weight)
2 cups buttermilk
1/4 cup plus 2 tablespoons vegetable oil
2 cloves garlic, bruised and skins removed
1 tablespoon crushed peppercorns
1 tablespoon Maldon salt, sea salt or 1 1/2 teaspoons table salt
1 teaspoon ground cumin
1 tablespoon maple syrup
Place the chicken drumsticks in a large freezer bag, and add the buttermilk and 1/4 cup of oil.
Add the bruised garlic cloves to the bag with the crushed peppercorns and salt.
Sprinkle in the ground cumin and finally add the maple syrup, and then squish everything in the freezer bag around to mix the marinade and coat the chicken.
Leave the buttermilk marinated chicken in the fridge ideally overnight or out of the fridge for at least 30 minutes and up to 2 hours.
Preheat the oven to 425 degrees F. Take the chicken pieces out of the bag shaking off the excess marinade, and then arrange them in a roasting tin lined with foil.
Drizzle over the 2 remaining tablespoons of oil, and then roast in the oven for about 30 minutes, or until brown, even scorched in parts, and juicily cooked through.