Preheat the oven to 375°F.
In a large pot, cover the potatoes with cold water and bring to a simmer. Simmer until soft but not mushy, about 16 to 20 minutes. Drain the cooked potatoes and return to the saucepan; place over a medium-low heat for 1 to 2 minutes to dry out the moisture, then mash using a potato masher. Quickly fold in the cream cheese, heavy cream, butter, sour cream and parmesan and season to taste.
Pat the pork chops dry with paper towels, brush with oil and season both sides with salt and pepper.
Heat a large skillet or grill pan over medium-high heat. When hot, add the pork chops and sear both sides until crisp and dark brown, about 2 minutes per side.
Transfer the seared pork chops to a baking sheet and finish cooking in the oven until they reach an internal temperature of 150°F, 12-15 minutes.
To make the mustard jus, combine the oil and flour in a medium pot over low heat, stirring. Cook for 7-10 minutes, until the flour is no longer raw-smelling. Add the chicken stock and cook for another 4-5 minutes, stirring. Add the salt, pepper, thyme and mustard.
For the brussels sprouts, melt the butter in a large skillet. When melted, add the shallots, reduce the heat to medium and cook until translucent, 2-3 minutes. Add the brussels sprouts and cook, stirring, until browned. Pour in the vinegar and deglaze, scraping up any browned bits on the bottom of the pan. Season to taste with salt and sprinkle with parsley.
To serve, divide the mashed potatoes and brussels sprouts between plates. Top with a pork chop and drizzle with mustard jus.