Preheat your oven to 350°F (175°C). Lightly grease a 9x9-inch baking pan or casserole dish with butter or oil. Spread half of the diced potatoes evenly across the bottom of the prepared dish. Layer the cubed chicken breasts over the potatoes, then season with ¼ teaspoon each of salt, paprika, and black pepper. Sprinkle half of the chopped bacon, ½ cup of shredded cheddar cheese, and half of the sliced green onions over the chicken layer. Add the remaining diced potatoes on top, followed by the rest of the bacon, another ½ cup of shredded cheese, and the remaining ¼ teaspoon each of salt, paprika, and pepper. Pour the heavy cream evenly over the entire casserole. *If the finished dish turns out too watery for your preference, you can reduce the amount of cream next time. Cover the dish tightly with aluminum foil and bake for 1 hour in the preheated oven. After 1 hour, remove the foil and bake uncovered for an additional 30 minutes. In the final 10 minutes of baking, sprinkle the remaining cheddar cheese and green onions over the top and continue baking until the cheese is melted and slightly golden. Remove from the oven and serve hot.