Lightly spray a 9x13 inch baking dish with cooking spray. Preheat your oven to 350°F (175°C).
In a large pot, cover the red potatoes with generously salted water. Bring to a boil and cook until the potatoes are easily pierced with a fork (fork-tender). Drain the water completely and return the potatoes to the pot.
Roughly mash the warm potatoes. Add the softened cream cheese, butter, crumbled bacon, 6 thinly sliced green onions, and 8 ounces of shredded cheddar cheese. Continue mashing gently until all ingredients are well combined and creamy.
Transfer the loaded mashed potato mixture into your prepared baking dish, spreading it out evenly to form the bottom layer.
Neatly spread the cooked pulled pork over the mashed potato layer.
Sprinkle the remaining 4 ounces of shredded Colby Jack cheese evenly over the pulled pork layer.
Cover the baking dish with aluminum foil and bake for 15 minutes. Then, remove the foil and continue baking for another 5 minutes, or until the cheese is melted, bubbly, and the casserole is heated through.
If desired, sprinkle with extra sliced green onions for a fresh pop of color and flavor. Serve this comforting casserole warm and enjoy!