Marinate the meat the night before. If needed, trim the skin off of the pork shoulder while you’re butterflying it, but don’t trim away the fat cap on top. We used a 4-pound piece off of a larger cut, so we also had a small bone to butterfly around.
Sprinkle evenly all over with salt (to avoid oversalting, sprinkle it from a height above the meat so it spreads evenly without needing to use a ton). Combine 1½ tablespoons ground fennel seeds, 1½ tablespoons dried thyme, 2 tablespoons dried oregano, and 1 tablespoon fresh minced rosemary leaves. Generously rub the meat all over with this seasoning. Next, stir together the 3 tablespoons of minced parsley and the minced garlic. Spread the majority on the inner parts of the butterflied pork shoulder, and distribute the rest on the top.
Rebundle the pork shoulder so it is in a relatively tight roll. Place in a roasting pan, and surround with the thinly sliced onion. Drizzle a little olive oil over the onions. Refrigerate overnight.
The next day, take your pork out of the refrigerator early (about 2 hours before you’re ready to roast) to come up to room temperature. Preheat the oven to 450 degrees F, and position a rack in the lower third of the oven, and one in the upper third.
You’re going to roast the pork and the peppers simultaneously, so wash the peppers, pat them dry, and cut them all lengthwise and deseed them (If you like your long hots really hot, skip that step!) Toss in olive oil, and sprinkle with salt. Lay out evenly on a baking sheet.
Place the roast in the lower third of the oven, and the peppers on the rack in the upper third. Roast at 450 degrees F for 35 minutes. After 35 minutes, remove the peppers from the oven and set them aside. Later, you can reheat the peppers by stirring them into the hot pulled pork to rewarm them, or by putting them back in the oven in the final stretch of cooking.
Also take the pork out of the oven at this step, and add the stock, wine, tomatoes, and bay leaves. Stir to combine. Cover the pan tightly with aluminum foil. Cook for another 15 minutes at 450 degrees F, and then reduce the oven temperature to 325 degrees F. Continue roasting the pork for 2 hours.
Carefully remove the foil (you'll be putting it back on). Using a sharp carving knife, cut the roast into large chunks, laying them flat in the braising liquid. Re-cover with foil and cook for another 2 to 2 ½ hours, until the pork is fork tender.
A little while before you take your pork out of the oven, it’s time to prepare your broccoli rabe. In a skillet over medium-high heat, add ¼ cup of olive oil and 7 cloves chopped garlic. Let the garlic brown lightly, and add the crushed red pepper flakes, followed by the chopped broccoli rabe. Cook until wilted, and then lower the heat if needed to cook until tender––you don’t want the stems to be crunchy!
Remove the pork from the oven. Discard the bay leaves. Pull the pork in the pan with two forks, mixing everything in the juices.
Stir in your reserved roasted peppers to rewarm them. Alternatively, you could reheat them in the oven in the last 10-15 minutes of roasting.
To build each sandwich, grab your Italian bread/rolls, and slice them lengthwise. Lay down a healthy bed of sharp provolone slices, and toast to melt the cheese. Top with a generous, drippy helping of pulled pork. Spoon over the broccoli rabe, and nestle a few pieces of long green hot pepper and bell pepper inside. Top off with pepperoncini slices if desired, and eat immediately!