Cut guanciale into strips and grate the pecorino cheese.

If you are using fresh tomatoes, bring a medium pot of water to a boil, add tomatoes and boil them less than a minute. Drain them and peel them (peel will come away easily at this point).

Heat a teaspoon of olive oil in a large skillet, add the chili and the guanciale.

Brown guanciale until crunchy. Add wine and vinegar, and cook, low heat, until alcohol evaporates (alcohol smell is gone).

Remove chili and a few tablespoons of guanciale. Discard the chili and set the guanciale aside.

Finally, add tomatoes and cook 10 minutes (add a few tablespoons of water if necessary).

Cook pasta al dente, drain it and pour it into the skillet, add 3/4 of the pecorino and sauté a minute or so.

Serve pasta hot, sprinkled with pecorino and the guanciale you kept aside.