1. Peel the onions, garlic, and carrot. Clean the celery. Finely chop all the vegetables.
2. Sweat the onions and garlic in oil. Then add the celery and carrot, let simmer for 5 minutes.
3. Add the meat and let it brown.
4. Once the meat has browned, add the peeled tomatoes and tomato paste, then the broth.
5. Reduce the heat, cover, and let simmer for 1/2 hour. Season with salt and pepper.
6. Cook the spaghetti according to the package instructions. Drain and distribute onto plates.
7. Pour Bolognese sauce over each plate, sprinkle with basil leaves, and serve.