Cook the guanciale in a skillet over low heat (no oil needed). Add the peperoncino and cook until the guanciale is golden. With a slotted spoon, remove the guanciale and set aside.
Turn up the heat, add the wine and cook until it evaporates and the alcohol flavor dissipates.
Turn the heat down, add the garlic and sautè for 30 seconds. Add the tomatoes. Mash the tomatoes with a large, wooden spoon (a potato masher also works well), season with salt and pepper and simmer over low heat, about 20 minutes.
Bring a pot of salted water to a boil. Drop in the pasta and cook until just al dente.
Add the reserved guanciale to the tomato sauce. Toss the cooked pasta with the sauce until well coated, 1 to 2 minutes.
Remove from the heat and add half the Pecorino. Toss/stir to combine.
Divide amongst bowls. Serve with extra grated Pecorino on top.
Notes
Guanciale (cured pork jowl) is traditional, but if you can't find it, your best option is pancetta (cured pork belly). If you can't find bucatini, you can substitute spaghetti.