1. In a small bowl, whisk together soy sauce, honey, chili-garlic sauce and ginger until well combined. Place pork shoulder in slow cooker, pour sauce over meat and stir to coat. Cover and cook on low until pork is tender, 7 to 8 hours.
2. Using a slotted spoon, transfer meat to a large bowl. Remove 1/2 cup sauce to a small bowl and whisk in cornstarch. Whisk cornstarch mixture back into slow cooker and cook, stirring once or twice, until thickened, about 5 minutes longer. Season with salt and pepper and pour over meat. Serve with rice, if desired.