Preheat the oven to 400°F (200°C) and line a baking sheet with parchment paper or grease it with olive oil.

Remove outer leaves from the cabbage and slice it into ¾-inch thick rounds to create 'steaks'.

In a mixing bowl, combine olive oil, garlic powder, smoked paprika, onion powder, thyme, salt, and black pepper.

Brush or spoon the seasoned oil mixture on both sides of each cabbage steak.

Place the seasoned cabbage steaks onto the prepared baking sheet in a single layer.

Roast the cabbage steaks for 25–30 minutes, flipping them after 15 minutes.

Remove from oven and optionally sprinkle with Parmesan, red pepper flakes, or parsley before serving.