Preheat the oven to 425 degrees Fahrenheit. Cut the spaghetti squash in half and remove the seeds and fibrous strands from each half. Lightly coat the cut sides of the squash with oil. Spray a baking sheet with oil and place the squash halves cut side down on the sheet. Bake for 30 to 40 minutes until the squash is tender and cooked through. Remove from the oven and let it cool, flipping the squash so the cut sides face up to speed cooling. Once cooled, use a fork to scrape the flesh into long strands and transfer to a bowl.

Heat olive oil in a large skillet over medium-high heat. Add the sliced zucchini and minced garlic, and sauté uncovered for about 3 minutes while stirring. Season with salt, then cover and continue cooking, stirring occasionally, for another 3 to 4 minutes until the zucchini softens and develops some browning. Depending on the size of your skillet, you may need to cook the zucchini in two batches.

Add the spaghetti squash to the skillet with the zucchini and stir to combine over low heat. Stir in the shredded Parmesan cheese and cook on low heat until the cheese melts. Season with salt and pepper to taste. Serve topped with toasted pine nuts.