1. Hollow out top and bottom halves of bread, leaving a 1/2-inch-thick shell; reserve torn bread for another use.
2. Combine cilantro, lime juice, chili powder, garlic, and black beans in a food processor; process until almost smooth and spreadable, adding a few drops of water, if necessary. Spread bean mixture evenly on bottom halves of the prepared rolls. Layer rolls evenly with ham, mango or tomatoes, and provolone cheese; replace top halves of rolls.
3. Heat 1 tablespoon olive oil in a large skillet over medium heat for 5 minutes. Add 2 sandwiches to pan; place a cast-iron or other heavy skillet on top of sandwiches; press gently. Cook 2 to 3 minutes on each side or until sandwiches are golden brown (leave cast-iron skillet on sandwiches while they cook). Remove sandwiches from pan; repeat procedure with remaining 1 tablespoon oil and 2 sandwiches.