Slice spaghetti sauce in half lengthwise and remove the seeds. Rub cut side of squash with a bit of olive oil, season with salt and pepper, and place cut side down on a rimmed baking sheet.
Bake until tender and easily pierced with a fork, about 40 minutes.
Meanwhile, stir together the garlic, Italian seasoning, heavy cream and Parmesan cheese in a small bowl. Season to taste with salt and pepper and set aside.
Once squash is cool enough to handle, fluff and separate strands of the squash with a fork.
Pour cream mixture over each half, stirring it into the strands, and top with mozzarella cheese.
Reduce heat to 350°F and bake until mixture is hot and bubbly, about 20 minutes. Enjoy!
