If you are starting with fresh tomato instead of canned, bring a pot of water to boil and then put them in the boiling water for a few minutes. Pour out into a colander to drain and cool them off under cold tap water. Remove the skins and then cut into slices and remove the seeds.
Refill the large pot with water and set back on the stove and bring to a boil again.
In a pan (preferably an iron skillet) heat the oil and add the guanciale cut into strips of about 1 or 2 centimeters long, stirring occasionally. If you are adding garlic or onion you can add it at this time, but this is optional to the recipe.
When the fat from the guanciale starts to melt, add the black pepper. Cook the guanciale until it has browned over medium heat, then simmer it with a generous splash of white wine. Let it evaporate, drain the pork cheek and set aside but keep warm.
In the same skillet, put the tomatoes that you prepared in step one (or canned or tomato paste although this is not our favorite option) and cook stirring for the same time as the pasta until the sauce thickens.
Add salt to the boiling water, then add the pasta and leave for the time indicated on the pasta box for al dente.
When the pasta is almost cooked, add the guanciale back into the sauce in the iron skillet and remove the chili pepper.
Drain the pasta when it is al dente and transfer it to the pan with the sauce and carefully stir until mixed well.
Turn off the heat and add the grated Pecorino Romano and fresh ground pepper to taste.
Mix well and serve immediately, sprinkling your pasta all'amatriciana with more grated Pecorino cheese on top if desired.