Pound the chicken breasts between sheets of plastic wrap to an even 0.5-inch thickness.
In a shallow bowl, whisk together the flour, salt, pepper, paprika, and garlic powder.
In a separate bowl, whisk the buttermilk and egg until combined.
Dredge each chicken breast in the flour. Dip into the buttermilk. Dredge again in flour, pressing to adhere.
Heat vegetable oil in a large skillet over medium-high heat until it reaches 350 degrees Fahrenheit.
Fry chicken for 4 to 5 minutes per side until the internal temperature reaches 165 degrees Fahrenheit.
Remove chicken and drain on a wire rack.
Discard all but 3 tablespoons of fat from the skillet. Add butter and whisk in 3 tablespoons of seasoned flour.
Gradually whisk in milk and simmer until thickened to create a cream gravy.
Season gravy with additional black pepper and serve over the fried chicken.