Preheat your oven to 400°F (200°C). Line a baking sheet with parchment paper or aluminum foil for easy cleanup.
Remove any tough outer leaves from the cabbage. Slice the cabbage into 1-inch thick rounds, making "steaks." Try to keep the core intact to hold the slices together.
Place the cabbage steaks on the prepared baking sheet. Brush each steak with olive oil, using about ½ Tablespoon per steak.
Season the cabbage steaks with salt and pepper to taste.
Transfer the baking sheet to the preheated oven and roast the cabbage steaks for 25 minutes, or until the edges are golden brown and crispy, and the cabbage is tender when pierced with a fork.
Remove the cabbage steaks from the oven and top with 1 Tablespoon parmesan cheese and 1 teaspoon balsamic vinegar on each steak.
Return to the oven and roast for an additional 5-8 minutes or until parmesan cheese is melted.
Remove from the oven and top with fresh parsley. Serve.