Heat a large nonstick skillet over medium heat. Coat pan with cooking spray. Add pork pieces; cook 4 minutes, browning on all sides. Add soy sauce, water, peppercorns, chicken, vinegar, broth, garlic, and bay leaf; bring to a boil. Cover, reduce heat, and simmer 1 hour. Uncover and increase heat to medium-high; simmer 20 minutes or until liquid is slightly syrupy. Discard bay leaf.