With a sharp knife, cut the head of cabbage down the middle, splitting it into two equal halves through the core. Place each half flat side down and slice in half again to create 4 quarters. Trim out the stem and tough core from each piece. Then, place each piece flat side down and thickly slice and then coarsely chop.

Slice the sausage into ½-inch pieces.

Heat 1 tablespoon oil in a Dutch oven over MEDIUM heat. Add the sausage and cook, stirring frequently, until browned, about 3 to 4 minutes. Transfer the browned sausage to a plate and set it aside.

Add the remaining 1 tablespoon oil to the pot and return it to MEDIUM-LOW heat. Add the onion and cook, stirring occasionally, until the onion has softened, about 5 minutes. Add the garlic and cabbage and season with the seasoned salt and pepper - the pot will be very full but the cabbage will cook down. Toss to combine. Reduce the heat to LOW, cover, and cook, for 5 minutes. Remove the cover and stir well to combine the cabbage with the onion. Cover and continue to cook for an additional 5 to 6 minutes or until the cabbage is wilted and fork tender.

Stir the vinegar into the cabbage then return the browned sausage to the pot. Stir and cook for an additional 2 to 3 minutes, uncovered until the sausage is heated through and the cabbage is tender. Taste and season with additional seasoned salt, only if needed. Garnish with parsley and serve.