Preheat oven to 375 degrees F.
Cook spaghetti noodles al dente according to package directions. Drain, then stir in one jar of marinara sauce until noodles are coated.
Heat 2 tablespoons olive oil in a large skillet or medium heat. Add diced onions and garlic and cook for 2-3 minutes until fragrant and translucent.
Add ground beef and Italian sausage to the pan and brown until it is no longer pink. Drain excess grease.
Stir in the second jar of marinara sauce and ½ tablespoon Italian seasoning. Simmer for a few minutes.
In a medium bowl, mix together ricotta cheese, cream cheese and the remaining Italian seasoning until smooth.
Spray a 9 x 13 baking dish with cooking spray. Layer half of spaghetti mixture on the bottom.
Then spread creamy cheese mixture evenly over the noodles. Add the remaining spaghetti, then meat sauce and top with parmesan and mozzarella cheeses.
Bake uncovered for 30 minutes or until the cheese is melted and bubbly.
Allow to cool for a few minutes before slicing and serving.