1. Preheat your oven to 400 F (200 C). Carefully cut the spaghetti squash in half lengthwise. Scoop out the seeds and stringy bits from the center using a spoon. Drizzle the cut sides with olive oil, and sprinkle with salt and pepper. Place the squash halves cut-side down on a baking sheet.

2. Roast the spaghetti squash in the preheated oven for 35-40 minutes, or until the flesh is tender when pierced with a fork. Once tender, remove from the oven and let it cool slightly until it’s comfortable to handle.

3. Once the squash has cooled a bit, use a fork to gently scrape the flesh from the sides of each squash half. It will naturally separate into spaghetti-like strands. Leave a small border of squash flesh attached to the skin to maintain the “boat” shape. Set the scraped squash aside in a bowl.

4. While the squash is roasting or cooling, prepare your alfredo sauce. In a medium saucepan over medium heat, melt the butter. Add the minced garlic and saute for about 1 minute until fragrant, being careful not to burn it.

5. Pour in the heavy cream and bring it to a gentle simmer, stirring occasionally. Reduce the heat to low and stir in the Parmesan cheese until it’s completely melted and the sauce is smooth and thickened. Season the sauce with salt and pepper to taste.

6. Add the cooked, shredded chicken and the reserved spaghetti squash strands to the alfredo sauce in the saucepan. Stir gently to combine everything, ensuring the chicken and squash are evenly coated with the creamy sauce.

7. Spoon the chicken alfredo mixture evenly back into the hollowed-out spaghetti squash halves. You can sprinkle a little extra Parmesan cheese on top if desired. Return the filled squash boats to the baking sheet and bake for another 10-15 minutes, or until the filling is heated through and bubbly.

8. Carefully remove the boats from the oven. Garnish with fresh chopped parsley, if using, and serve immediately.