In a large bowl, mix the buttermilk with half of the flour, paprika, black pepper, and salt. Add the chicken pieces and marinate for at least 1 hour.
Heat the vegetable oil in a large skillet over medium-high heat.
Remove the chicken from the marinade and dredge in the remaining flour. Shake off excess.
Fry the chicken in the hot oil, turning occasionally, until golden brown and cooked through, about 15-20 minutes. Remove and drain on paper towels.
For the gravy, melt the butter in a saucepan over medium heat. Stir in 2 tablespoons of the leftover flour mixture from the chicken dredging.
Gradually whisk in the milk, bring to a simmer, and stir continuously until the gravy thickens. Season with salt and additional black pepper to taste.
Serve the fried chicken with the creamy gravy poured over the top or on the side.