Step 1: Roast the Spaghetti Squash : Preheat oven to 400°F (200°C). Cut spaghetti squash in half lengthwise and scoop out seeds. Brush the cut sides with olive oil, and season with salt and pepper. Place cut-side down on a baking sheet and roast for 30–35 minutes, or until tender. Let cool slightly, then use a fork to scrape the flesh into spaghetti-like strands.

Step 2: Prepare the Garlic Parmesan Sauce : In a large skillet, melt butter over medium heat (or heat olive oil). Add minced garlic and red pepper flakes (if using), sauté for 1–2 minutes until fragrant. Stir in broth, heavy cream (if using), and Parmesan cheese, stirring until smooth. Season with salt and black pepper to taste.

Step 3: Combine Spaghetti Squash and Sauce : Add roasted spaghetti squash strands to the skillet. Toss gently to coat evenly with the garlic Parmesan sauce. Cook for 2–3 minutes to heat through, allowing sauce to thicken slightly.

Step 4: Serve : Plate the spaghetti squash and garnish with fresh parsley and extra Parmesan cheese. Serve hot as a main dish or side.