Pat the pork shoulder pieces dry. In a small bowl combine 1 tsp salt, 1 tsp black pepper, 1 tsp smoked paprika, 1 tsp onion powder and 1 tsp garlic powder; rub over the pork. Heat 2 tbs olive oil in a large heavy pot or Dutch oven over medium-high heat. Brown the pork on all sides, 3–4 minutes per side, working in batches so pieces don’t steam. Transfer browned pork to a plate.

Braise

Reduce heat to medium. Add 1 cup water or stock to the pot, scraping up browned bits. Stir in 1 cup BBQ sauce, 2 tbs apple cider vinegar and 2 tbs brown sugar. Return pork to the pot, bring to a gentle simmer, cover, and reduce heat to low. Braise until very tender, about 2 to 2 1/2 hours (or 4–6 hours on low in a slow cooker). Check occasionally and add a few tablespoons of water if liquid reduces too much.

Shred and finish

When pork is fork-tender, remove to a cutting board and shred with two forks. Skim excess fat from the braising liquid; reserve about 1/2 cup of the cooking liquid. Toss shredded pork with reserved braising liquid and an additional 1/4 cup BBQ sauce to taste. Keep warm until assembly.

Macaroni & Cheese

Cook pasta

Bring a large pot of salted water to a boil. Add 1 lb macaroni and cook until just shy of al dente (about 1–2 minutes less than package instructions). Reserve 1/2 cup pasta water, then drain and set aside.

Make roux

In the same pot, melt 4 tbs butter over medium heat. Whisk in 4 tbs flour and cook, whisking, for 1–2 minutes until a pale blonde roux forms (do not brown).

Add milks

Gradually whisk in 2 cups whole milk and 1 cup buttermilk until smooth. Bring to a gentle simmer, whisking constantly, until sauce thickens enough to coat the back of a spoon, about 4–6 minutes.

Finish cheese sauce

Reduce heat to low. Whisk in 4 oz cream cheese until melted and smooth. Stir in 3 cups sharp cheddar and 1 cup white cheddar a handful at a time until melted. Add 1 tsp Dijon mustard, 1 tsp hot sauce (optional), 1 tsp salt, 1/2 tsp black pepper and 1/8 tsp nutmeg. If sauce is too thick, whisk in reserved pasta water 1–2 tbs at a time to reach desired creaminess.

Combine with pasta

Add drained pasta to the sauce and fold until evenly coated. Taste and adjust seasoning. Transfer about 6 cups of the mac & cheese to an ovenproof baking dish, reserving any extra for another use.

Ritz Crumble Topping

Preheat oven to 375°F (190°C). In a medium bowl combine 1.5 cups crushed Ritz crackers, 4 tbs melted butter, 1/4 cup grated Parmesan, 1/2 tsp smoked paprika and 1/4 tsp salt. Stir until crumbs are evenly moistened. Set aside.

Buttermilk Fried Onions

Soak onions

Place thinly sliced onion rings in a bowl and cover with 1 cup buttermilk. Let soak for 15–20 minutes to tenderize and pick up tang.

Dredge

In a shallow bowl whisk together 1 cup flour, 2 tbs cornstarch, 1/2 tsp salt and 1/4 tsp black pepper. Heat 2 cups vegetable oil in a wide, heavy skillet (or fryer) to 350°F (175°C). One handful at a time, lift onion rings from buttermilk, letting excess drip, then dredge in the flour mixture, shaking off excess.

Fry

Fry onions in batches in the hot oil until golden brown and crisp, about 2–3 minutes per batch. Use a slotted spoon to transfer to a wire rack or paper towel-lined tray. Season immediately with a light pinch of salt. Keep warm or re-crisp in a 300°F (150°C) oven for a few minutes before serving.

Assembly & Bake

Preheat oven to 375°F (190°C) if not already on. Stir 2 cups pulled BBQ pork and 1/4 cup additional BBQ sauce gently into the prepared macaroni & cheese in the baking dish so pork is evenly distributed but sauce is not overpowering.

Evenly sprinkle the Ritz crumble topping over the mac & cheese with pork. Bake uncovered for 18–22 minutes, until topping is golden and the filling is bubbling around the edges.

Remove from oven and let rest 5 minutes. Top with a generous handful of buttermilk fried onions and 2 tbs chopped chives or parsley. Serve hot with extra BBQ sauce on the side.