In a small bowl, whisk together olive oil, garlic salt, and pepper.
Using gloved hands, rub the oil and spice mixture all over the short ribs.
Preheat a skillet over medium high heat. Do not add any oil. When skillet is hot, sear the short ribs to develop a nice brown crust.
Line a square baking pan or casserole dish with foil and spray with cooking spray. Place ribs in prepared pan and cover tightly with foil.TIP - Do not uncover pan until 3 1/2 hours has passed to keep heat inside. After checking for doneness you can recover and continue baking for 30 more minutes.
Bake in oven for 3 1/2 - 4 hours, or until meat is easily pulled away with a fork.