Pour the oil into a large ovenproof roaster about 9 × 13 inches and place in the oven to get hot during preheating.
When the oil is hot, add the meat and onion and bake, uncovered, for about 15-20 minutes or until meat is browned; reduce heat to 350°.
In a small bowl, mix together the soy sauce, vinegar, garlic, bay leaves, and 1 cup of the water.
Pour onto the meat.
Cover the roaster and bake for 30 minutes more or until the meat is cooked through and tender.
With a slotted spoon, remove the meat to another dish and keep warm.
Pour drippings from the roaster into a saucepan, remove bay leaves, and allow drippings to sit undisturbed for several minutes to give the fat time to rise to the top.
Skim off as much as you can.
Turn on heat, bring drippings to a boil and boil until liquid has been reduced to 1 cup.
(Just eyeball it—no need to measure.
)
Mix together the cornstarch and 1 T.
water and pour it into the drippings, stirring constantly.
Continue to stir constantly until the mixture thickens.
Pour over the meat and gently mix to coat all pieces.
To serve, spoon some hot cooked rice onto plates or into bowls, ladle pork on top of rice, and sprinkle with green onions.
