Add the oil to a small saucepan. Fry off the prepared shallot, carrot, and celery for 5 minutes.
Add the garlic clove in it whole form.
Fry off the mince until coloured all over and add the Bolognese sauce . Scatter in the celery leaves.
Add the Parmigiano Reggiano rind and season with salt, pepper, oregano, and chilli.
Cook for 90 minutes.
To finish, add the lemon zest for a touch of freshness and tender fresh basil leaves.
Cook the spaghetti until aldente and dress with the sauce and grated Parmigiano Reggiano.