• Preheat oven to 400 degrees.

Make the Alfredo Sauce

• Bring a large pot of salted water to a boil while preparing the alfredo sauce. In a large skillet over medium low heat, melt 6 tablespoons of butter. Add in the garlic and stir until fragrant.
• Pour in the cream and bring to a low boil then simmer about 5 minutes, allowing the cream to thicken. Add in the parmesan cheese and cream cheese, whisk until melted and the sauce is thicken (it will continue to thicken more as it cools).
• Season the alfredo sauce with salt to taste, red pepper flakes and freshly cracked pepper.
• Add the pasta to the boiling water and cook to al dente. Strain and return to the pot, then pour in the alfredo sauce and toss until the pasta is evenly coated. Clean out the alfredo skillet as we'll reuse this for browning the meat.

Brown the Meat

• Into the skillet over medium heat add 1 tablespoon of olive oil. Add in the beef and sausage, mincing it as it cooks. After about 2 minutes add in the peppers, onions and garlic and saute while the meat cooks.
• Pour in the marinara sauce, Italian seasonings and salt and pepper to taste. Stir it together so the sauce evenly incorporates.

Bake The Spaghetti

• Into a greased large cast iron skillet or 9x13 casserole dish, add the alfredo smothered spaghetti and spread it evenly. Pour over the marinara meat sauce on top of the spaghetti, leveling it out with a spatula.
• For the final layer, add shredded cheese over the entire top of the baking  dish. Bake for 20 minutes and optionally, broil for an additional 5 minutes.