Using a fork, poke holes all over your brisket. Then rub the entire surface of the brisket with 1 tablespoon salt. Wrap the salted brisket in plastic wrap and refrigerate for at least 6 hours - best results allow 24 hours.

Preheat your oven to 325 degrees F. Place your oven rack to the lower-middle position.

With paper towels pat the brisket dry and then season with pepper. In a non-stick skillet heat 2 teaspoons of oil over medium-high heat - just to the smoking point. Place your brisket fat side down in the skillet and weigh down the brisket with a heavy dutch oven or a cast iron skillet and allow to cook until well browned. This should take about 4 minutes.

Remove the dutch oven, flip the brisket and repeat. Once it is completely browned, transfer the brisket to a plate.

Heat the remaining 2 teaspoons of oil in the empty skillet over medium-high heat until it shimmers. Add the onions, stir occasionally until they turn a soft and golden brown color, this will take about 12 minutes. Transfer these onions to a baking dish 13x9 in an even layer.

Combine the coke, ketchup, onion powder, sugar, garlic powder, thyme with 1 teaspoon salt and 1 teaspoon of pepper in a small bowl. Place the brisket fat side up on top of the layer of onions and pour your coke mixture over the brisket. Place parchment paper over the brisket and cover tightly with aluminum foil. Bake the brisket until a fork easily slips in and out of the meat - this can take up to 3 1/2 to 4 hours. Allow the brisket to rest in the liquid, uncovered for at least 30 minutes.

Transfer the brisket to a carving board. Skim any fat from the top of the sauce with a large spoon. Slice the brisket against the grain into 1/4 inch thick slices and then return to the baking dish. Serve the brisket with the sauce.