Combine first 8 ingredients in a small bowl; stir until well-blended. Set aside.
Trim fat from pork. Cut pork into 1-inch cubes. Combine pork, 1 tablespoon cornstarch, and 1 tablespoon soy sauce in a bowl; stir well. Cover and marinate in refrigerator 15 minutes.
Heat 1 teaspoon vegetable oil in a wok or large nonstick skillet over high heat. Add chiles; stir-fry 1 minute or until blackened. Remove from pan with a slotted spoon; set aside. Add remaining oil and pork mixture to pan; stir-fry 2 minutes. Add bell pepper, onion, and gingerroot; stir-fry 1 minute or until vegetables are crisp-tender. Add sherry mixture; stir-fry 1 minute or until thick and bubbly. Remove from heat; stir in chiles and peanuts. Serve over rice.