For the gravy: Melt the butter in a large saucepan over medium heat. Once the butter is melted and foamy, stir in 1/4 cup flour and cook until pasty, 1 to 2 minutes.
Slowly whisk in the milk, making sure there are no lumps. Bring to a boil over medium heat, stirring frequently.
Season the sauce with nutmeg, a pinch of salt and black pepper. Reduce the heat and simmer for 10 minutes, stirring occasionally.
For the potatoes: Preheat the oven to 350°F. Spray a 9- by 9-inch casserole dish with nonstick spray.
Layer a third of the potatoes into the casserole dish. Top with a third of the shallots and sprinkle lightly with salt and black pepper. Repeat with the remaining potatoes and shallots, a third at a time. Cover the potatoes with the black pepper white gravy and bake, covered in tinfoil, for 25 minutes.
For the pork chops: Heat the vegetable oil in a large cast-iron skillet over medium-high heat.
Combine remaining 1/2 cup flour, paprika, garlic powder, onion powder and cayenne together in a pie plate. Sprinkle the pork chops on both sides with salt and black pepper, and then dredge them through the flour mixture. Add the pork chops to the hot oil and brown on both sides. You do not want to cook them all the way through.
Remove the casserole dish from the oven and lay the chops on top of the potatoes. Bake until the potatoes are soft and the pork chops are cooked through and browned, 35 to 40 minutes. Serve with some chopped parsley sprinkled over the top if desired.