Gather lemon peel strips, sage, thyme, and peppercorns together in an 8-inch-square piece of dampened cheesecloth to create a purse-style sachet; tie to close using kitchen twine. Set aside.

Heat oil in a large Dutch oven over medium-high. Sprinkle pork evenly with 1 ½ teaspoons salt and ½ teaspoon black pepper; add to Dutch oven. Cook, turning occasionally, until meat is browned on all sides, about 8 minutes. Using a slotted spoon, transfer pork to a plate. Reserve ¼ cup drippings in Dutch oven; discard remaining drippings. Add wine to drippings in Dutch oven; simmer over medium-high, scraping any browned bits from bottom of Dutch oven and stirring occasionally, until liquid is reduced to about 1 cup, about 5 minutes.

Return pork to mixture in Dutch oven. Add reserved sachet, beans, garlic head, broth, cream, and baking soda. Stir in milk. Bring to a simmer over medium-high, stirring often. Reduce heat to medium-low; cover and cook, stirring occasionally, until pork and beans are tender but not yet falling apart, 2 hours to 2 hours and 30 minutes. (Begin checking pork and beans after 1 hour and 30 minutes of cooking. If pork is tender before beans, use a slotted spoon to transfer pork to a bowl while beans finish cooking.) Add kale, if using, and cook, covered, until wilted and tender, about 10 minutes. Remove and discard sachet. Stir remaining 1 teaspoon salt and remaining ½ teaspoon pepper into bean mixture; add additional salt and black pepper to taste. Garnish with chopped parsley and crushed red pepper. Serve with crusty bread.