Dredge pork in cornstarch.
Heat 2 tablespoons oil in a wok or large skillet over medium-high heat; stir-fry pork in batches, 3 minutes or until browned. Remove pork from skillet; set aside.
Drain pineapple, reserving 1/4 cup juice. Add reserved juice and soy sauce to skillet, stirring to loosen browned particles.
Add remaining 1 tablespoon sesame oil to skillet; stir-fry pineapple, bell peppers, and green onions 5 minutes or until peppers are tender.
Stir together hoisin sauce and garlic-chili sauce; add to skillet. Add pork, and stir-fry 5 minutes. Serve over rice. Sprinkle with sesame seeds.
Note: For testing purposes only, we used A Taste of Thai Garlic Chili Pepper Sauce.