Directions

1. In a small bowl, stir together 1/3 cup pineapple juice, vinegar, soy sauce, cornstarch, and 1/4 cup water. Season sauce with salt and pepper.
2. In a large nonstick skillet, heat 1 tablespoon oil over medium-high. Cook pork, in two batches, until well browned on one side, about 1 minute (pork will cook more later); transfer to a plate.
3. To skillet, add scallion whites and bell peppers; season with salt and pepper. Cook, stirring, until peppers are crisp-tender, 6 to 8 minutes.
4. Add pork (along with any juices), broccoli, and pineapple chunks. Whisk sauce; add to skillet. Bring to a simmer; cook, stirring, until broccoli is warmed through, 2 to 4 minutes. Stir in scallion greens, and serve with rice.