Combine the first 9 ingredients in a slow cooker. Set slow cooker to high to preheat.
Heat 2 tablespoons oil in a large skillet or sauté pan over medium-high heat.
Generously season beef short ribs with salt and black pepper. Add short ribs to pan, reduce heat to medium and brown well on all sides, approximately 2-3 minutes per side.
Transfer ribs, meat side down, to slow cooker.
Cover and cook on HIGH for 4-6 hours or LOW for 8-10 hours or until very tender.
Combine cornstarch with approximately 4 tablespoons of the cooking liquid in a small bowl and stir until smooth. Pour cornstarch mixture into slow cooker, stir to blend and cook uncovered on high for approximately 20 minutes.
Turn slow cooker off and let stand 10 minutes. (Sauce will thicken more upon standing.)
Heat remaining 1 teaspoon oil in a skillet or sauté pan over medium-high. Cook scallions, 2-3 minutes or until slightly softened and browned.
Serve short ribs with scallions, kimchi, cooked brown rice and shredded carrots.