Ingredients

• 2 1/2 pound boneless pork shoulder (Boston butt)
• 8 garlic cloves, 4 halved, 4 finely chopped
• 2 teaspoons kosher salt plus more
• 1 cup torn 1" pieces day-old crusty white bread
• 6 tablespoons olive oil, divided
• 1 tablespoon finely grated lemon zest
• 1 tablespoon finely grated orange zest
• 1/2 teaspoon crushed red pepper flakes
• 1 15-ounce can cannellini (white kidney) beans, rinsed
• 1/2 cup finely grated Parmesan, divided, plus more
• Freshly ground black pepper
• 2 bunches turnip greens or kale, center ribs and stems removed, leaves coarsely chopped
• 1 pound fettuccine

Instructions

1. Place pork in a large roasting pan. Using a paring knife, make 8 evenly spaced slits in pork; slide 1 garlic clove half into each. Season pork with 2 teaspoons salt, cover with plastic wrap, and chill at least 1 hour or up to overnight.
2. Preheat oven to 325°F. Uncover pork and roast until very tender, 3 1/2-4 hours. Let cool. Shred pork and set aside.
3. Pulse bread in a food processor until coarse crumbs form. Heat 2 tablespoons oil in a medium skillet over medium heat. Add breadcrumbs and cook, stirring often, until golden brown, about 5 minutes. Add lemon and orange zests and red pepper flakes, and cook, stirring, just until fragrant, about 1 minute. Transfer citrus breadcrumbs to a paper towel-lined plate and let cool.
4. Bring beans, 1/4 cup Parmesan, and 2 cups water to a boil in a small saucepan. Reduce heat and simmer until flavors meld, 5-8 minutes. Season with salt and pepper.
5. Heat remaining 4 tablespoons oil in a large pot over medium heat. Add chopped garlic and cook, stirring, until fragrant but not browned, about 1 minute. Add greens and cook, stirring occasionally, until tender, about 5 minutes. Add beans with their cooking liquid and reserved pork.
6. Meanwhile, cook pasta in another large pot of boiling salted water, stirring occasionally, until al dente. Drain pasta, reserving 1 cup pasta cooking liquid.
7. Add pasta and 1/2 cup pasta cooking liquid to greens. Cook over medium-high heat, stirring; add more pasta cooking liquid as needed until sauce coats pasta. Stir in 1/4 cup Parmesan. Top with breadcrumbs and more Parmesan.
8. DO AHEAD: Pork can be roasted and shredded 2 days ahead. Cover; chill. Citrus breadcrumbs can be made 1 day ahead; store airtight at room temperature.