• Preheat oven to 400°F.
• Cut spaghetti squash in half lengthwise, scoop out seeds, and brush the cut sides with olive oil.
• Sprinkle with salt and pepper. Place cut-side down on a baking sheet and roast for 35–40 minutes, or until tender.
• Using a fork, scrape the spaghetti squash flesh into strands but leave the shells intact.

To make the filling:

• While the squash is cooking, in a large skillet, melt butter over medium heat. Add garlic and cook 30 seconds, until fragrant.
• Stir in heavy cream, Parmesan, cream cheese, and Italian seasoning. Whisk until smooth and slightly thickened, about 3-4 minutes.
• Add spaghetti squash strands and chicken to the skillet with the sauce. Toss gently to coat and cook for 1-2 minutes more, or until heated through.
• Spoon the Alfredo mixture evenly into the spaghetti squash shells. Top with shredded mozzarella.
• Broil for 1–2 minutes until cheese is golden and bubbly. Serve topped with fresh chopped parsley.