Boil the Pasta: Bring a large pot of salted water to a rolling boil. Add the spaghetti noodles and cook until al dente, about 8-10 minutes. Reserve ½ cup of pasta water, then drain and set aside.

Sauté the Beef: In a skillet, heat olive oil and unsalted butter. Add ground beef, Cajun seasoning, garlic powder, and onion powder. Sauté for 5-7 minutes until browned. Transfer beef to a plate, leaving drippings.

Create the Creamy Base: Reduce heat and add heavy cream and cream cheese to the skillet. Stir until smooth and creamy.

Incorporate the Cheeses: Gradually add mozzarella and Parmesan cheese, stirring until melted. If sauce is thick, add reserved pasta water.

Combine Everything: Return the beef and spaghetti to the skillet. Toss to coat in sauce, simmer for 1-2 minutes.

Garnish and Serve: Remove from heat, garnish with parsley, and serve warm, with extra Parmesan or Cajun seasoning if desired.