Buttermilk Soak

3 cups buttermilk
2 tablespoons kosher salt
1 tablespoon freshly ground black pepper
2 teaspoons cayenne pepper
4 pounds medium chicken wings, thighs and drumsticks

Beer Batter

2 cups all-purpose flour
2 teaspoons onion powder
2 teaspoons garlic powder
2 teaspoons cayenne pepper
2 teaspoons kosher salt
2 teaspoons freshly ground black pepper
18 ounces crisp beer, such as lager or pilsner (2 1/4 cups)
Vegetable oil, for frying