1. Coat a large nonstick skillet with cooking spray; place over medium-high heat until hot. Add pork and garlic; cook 3 minutes or until pork is done, stirring often.
2. Combine orange juice and next 3 ingredients in a small bowl, beating with a wire whisk until blended.
3. Wash lettuce leaves; arrange on a serving platter. Arrange beans, pork, and orange sections over lettuce leaves. Drizzle with orange juice mixture, and sprinkle with green onions.