Put a large pan of salted water for the pasta on the stove to heat while you're making the sauce.
In a large frying pan, heat the oil over a moderate heat. Add the pancetta and fry for 4 minutes until just beginning to crisp.
Stir in the onion, celery and garlic and fry for 4-5 minutes until the onions are soft.
Add the oregano and the chilli flakes and stir in.
Pour in the wine and let it sizzle for 30 seconds or so until the alcohol has burned off. Season with salt & pepper.
Now add the tomato. Stir well and let this come to a simmer before adding a little chicken stock or water to thin out the sauce a little. Simmer gently over a low heat for 10 minutes then remove from the stove.
When the pasta water is boiling, cook the pasta to the packet instruction minus about 1 minute. Drain and add directly to the pasta sauce over a moderate heat. Toss it around then add a handful of grated parmigiano reggiano mix in. Remove from the heat and you're ready to serve.