Oven to around 410 degrees. Line a cookie sheet with parchment.
Lay the cabbage slices out on the cookie sheet. Drizzle with a little olive oil on each slice, sprinkle lightly with sea salt and generously with the nutritional yeast.
Roast until the cabbage seems soft, with some light brown around the edges. This often takes me 20 minutes. Watch carefully so it doesn't burn.