In a small bowl, combine the garlic, oregano, thyme, salt, pepper and olive oil. Set aside.
If your pork loin came tied, remove the twine. Then on a clean, dry surface, use a boning knife to trim the pork of some of the excess fat -- Sara recommends leaving about ¼ inch, if possible. Next, use a Chef's knife to butterfly the pork loin in a roll cut. (See images above recipe.)
Sprinkle the butterflied pork very lightly with water, and then place a piece of plastic wrap on top. Use a smooth meat pounder or the bottom of your smallest sauté pan to pound the pork until it's ½ to 1 inch thick.
Mix the marinade and pour about half of it in the bottom of a 9 X 13 inch baking dish. Place the butterflied, pounded pork on top, and then drizzle the rest of the marinade over it. Use your hands to rub the marinade into the pork, being sure it's completely coated on both sides. Cover with plastic wrap and place in the refrigerator overnight.
Preheat the oven to 450°F and remove the pork from the fridge.
Place the pork, fat side down (cut side up), on a clean, dry surface, with the short end facing you. Arrange the salami in an even layer, leaving about a 1 inch border at the short end furthest from you. Add the spinach in an even layer, followed by the provolone slices, and topped with the peppers. (See pictures above the recipe.)
Now, starting with the end closest to you, roll up the pork, as tightly as possible. With the seam side down, use butcher's twine to tie the pork.
Return the now stuffed pork to the baking dish and place it in the 450°F oven and roast for 15 minutes. Then reduce the heat to 325°F, and roast until the internal temperature is 140°F, about 20 minutes.
Remove from the oven and let it rest, covered loosely with foil, for at least 25 minutes, before slicing.