Preheat your oven to 400°F (200°C).
Microwave the whole spaghetti squash for 2–3 minutes to soften slightly for easier cutting.
Carefully cut the squash lengthwise and scoop out the seeds using a spoon.
Drizzle the inside with olive oil and season lightly with salt and pepper.
Place the squash halves cut-side down on a baking tray.
Roast for 35–45 minutes, or until the flesh is tender and easily separates into strands with a fork.
Remove from the oven and let it cool for 5–10 minutes.
Use a fork to gently scrape the inside to create spaghetti-like strands.
Heat 2 tablespoons olive oil in a large pan over medium heat.
Add minced garlic and cook for about 30 seconds until fragrant.
Stir in oregano, chili flakes (if using), salt, and black pepper.
Add the spaghetti squash strands to the pan and toss gently to combine.
Mix in parmesan cheese and any optional add-ins like cooked chicken, vegetables, or ground meat.
Cook for another 2–3 minutes until everything is heated through.
Serve warm and enjoy.