Step 1: Preheat your oven to 400°F (200°C) and line a large baking sheet with parchment paper for easy cleanup.
Step 2: Slice the spaghetti squash in half lengthwise. If it is too hard to cut, microwave it for 2-3 minutes first to soften the outer skin.
Step 3: Use a metal spoon to scrape out the seeds and any pulpy bits from the center of each squash half.
Step 4: Drizzle the flesh with 1 tablespoon of olive oil and sprinkle with salt and pepper. Rub the oil and seasoning into the flesh until evenly coated.
Step 5: Place the squash halves cut-side down on the prepared baking sheet. Roast for 40-50 minutes, or until the skin is easily pierced with a fork and the edges are slightly browned.
Step 6: While the squash is roasting, heat the remaining 2 tablespoons of olive oil in a small skillet over medium-low heat. Add the minced garlic and cook for 1-2 minutes until fragrant and golden, being careful not to burn it.
Step 7: Remove the squash from the oven and let it rest for 10 minutes. Use a fork to gently scrape the flesh into long, noodle-like strands, keeping them inside the squash skin or transferring to a bowl.
Step 8: Pour the garlic oil over the strands and toss gently. Sprinkle with parmesan cheese and fresh parsley. Serve immediately while hot.