1. Preheat the oven to 400°F (200°C).

2. Peel and chop the butternut squash into small cubes.

3. Place the butternut squash cubes on a baking sheet, drizzle with olive oil, and season with salt and pepper. Roast in the preheated oven for 25-30 minutes or until tender.

4. Meanwhile, cook the spaghetti according to package instructions. Drain and set aside.

5. In a large skillet, heat some olive oil over medium heat. Add the red onion and cook until softened.

6. Add the ground beef to the skillet and cook until browned. Season with salt, pepper, and any other desired spices or herbs.

7. Once the butternut squash is roasted, add it to the skillet with the ground beef and red onion. Mix well.

8. Add the cooked spaghetti to the skillet and toss everything together until well combined.

9. Serve hot and enjoy!