Cuban Pork Tacos With Orange Slaw

Name: Cuban Pork Tacos With Orange Slaw
Ingredients: 3 navel oranges; ¼ cup fresh lemon juice (from 2 lemons); 8 cloves garlic, smashed; 4 ½ teaspoons kosher salt, divided; ¾ cup chopped fresh cilantro leaves, divided; 1 ¼ teaspoons freshly ground black pepper, divided; 1 3-lb. boneless pork shoulder (Boston butt), cut into 4 pieces; ½ small head green cabbage, shredded; 1 small yellow onion, thinly sliced; 2 tablespoons olive oil; 2 tablespoons white wine vinegar; 1 15-oz. can black beans, drained and warmed; 12 6-in. corn tortillas, warmed