Makes 6 sandwiches
In the bowl of a blender or food processor, combine 1/2 cup olive oil with sage, fennel fronds, thyme, rosemary, oregano, shallot, minced garlic, orange and lemon zests, fennel seeds, coriander, white wine, 1 1/2 teaspoons salt, and 1 teaspoon pepper and process for 45 seconds or until ingredients are well combined.
Lay pork skin side down on a cutting board, and using a meat mallet or a Jaccard meat tenderizer, pound pork. Spread herb-olive oil mixture all over pork. Roll pork like a jelly roll and then tie it with butcher's twine. Place pork on a sheet pan and refrigerate overnight.
Preheat oven to 500 degrees.
Remove pork from refrigerator and allow it to come to room temperature. Rub outside of roast with 3 tablespoons olive oil and then season pork with 1 1/2 tablespoons salt and 2 teaspoons pepper. Place pork in a medium roasting pan. (The pan should just be slightly bigger than the roast.) Place pork in oven and immediately reduce temperature to 250 degrees. Roast pork for 4 to 4 1/2 hours, uncovered. (Pork should reach an internal temperature of 165 degrees.) If the skin does not seem crisp at the end of 4 1/2 hours, increase heat to 450 degrees and continue to roast for 15 minutes or up to 30 minutes to form a crispy crust.
Remove pork from oven and let rest for 20 minutes. Slice into 1-inch-thick pieces.
In a large saute pan over medium-high heat, add remaining 2 tablespoons olive oil and 2 cloves sliced garlic and cook for 30 seconds or just until garlic is fragrant. Add dandelion greens in batches and cook until just wilted. Season with 1/4 teaspoon salt.
Lay one slice of pork on toasted bread and spoon about 1 teaspoon pan juices over the pork. Season with salt and pepper, drizzle with extra-virgin olive oil, and top with a mound of dandelion greens. Serve immediately.
The pork roast will yield more meat than is necessary for the sandwiches, but it makes great leftovers and can be refrigerated in a resealable container for 3 to 5 days.