Preheat the oven to 3500 F. Bring a large pot of salted water to a boil. Cook the spaghetti until al dente, according to package directions. Drain and toss the pasta with butter.

Meanwhile, in a Dutch oven set over medium heat, add the sausage, beef, onion, bell peppers, and Italian seasoning. Brown all over for 10 minutes. Add the tomatoes and 1 cup of water. Season with salt, pepper, and chili flakes. Simmer for 10 minutes, until just slightly thickened. Add the sun-dried tomatoes and basil. Remove from the heat.

In a bowl, mix the cream cheese, ricotta cheese, and parmesan. Season with salt and pepper.

In a large casserole dish, layer 1 cup of the meat sauce with the spaghetti, white sauce, and remaining meat sauce. Top with mozzarella, provolone cheese, and the pepperoni. Bake for 30 minutes, until the cheese is melted. Let sit for 10 minutes. Top with fresh basil, and enjoy!