Preheat and prep: Firtsly, preheat your oven to 350°F and grease a 9x13-inch baking dish.
Prepare the pasta: In a large pot, cook 1 lb elbow macaroni according to package directions until al dente, then drain and place in your greased baking dish.
Make the cheese sauce: In a medium saucepan, melt 4 tbsp butter over medium heat. Add 4 tbsp flour, ½ tsp salt, and 1 tsp sugar, stirring until smooth. Gradually whisk in 2 ½ cups milk and bring to a boil, then cook for 2 minutes until thickened. Stir in 8 oz Velveeta cheese until melted, then add ½ cup cottage cheese, ½ cup sour cream, and 1 cup cheddar cheese until everything's melted and creamy.
Combine and layer: Pour the cheese sauce over the macaroni in your baking dish. In a bowl, mix 2 cups pulled pork with ¼ cup barbecue sauce, then spoon evenly over the mac and cheese.
Top and bake: Sprinkle the remaining 1 cup cheddar cheese on top. Bake covered for 20 minutes, then uncover and bake 20 more minutes until heated through and bubbly.
Finish and serve: Let it rest for 5 minutes, then sprinkle with fresh parsley if you want before serving.