extra-virgin olive oil, as needed for greasing the pan
1/2teaspoonfine sea salt
Preheat the oven to 450ºF and grease a baking sheet with olive oil.
Remove the green leaves from the head of cauliflower and cut off any excess stem. Slice off one side of the cauliflower, right at the edge of the stem in the center. (Reserve the extra cauliflower scraps for another use.)
Cut the cauliflower into slabs, right through the center of the stem, that are roughly 3/4- to 1-inch thick. You should be able to get 2 to 3 steaks per large head of cauliflower. Be careful not to cut the steaks too thin, or they could fall apart.
Place the 3 cauliflower steaks on the baking sheet and drizzle them lightly with olive oil on both sides. Season evenly with the garlic powder, onion powder, paprika, and salt on both sides. (I like to use a brush, or rub the seasoning in with my hands, to make sure every nook and cranny of the cauliflower is well seasoned.) You can mix the seasonings in a small bowl first to make a seasoning mix, or just sprinkle each one over the cauliflower individually to avoid having an extra dish to clean later.
Place the pan in the oven for the cauliflower to roast for 15 minutes. When the timer goes off, use a spatula to flip over each steak, and then return the oven to roast until fork-tender, about 10 to 15 minutes more. The steaks should be golden on both sides, and the center stem should be easily pierced by a fork.
Serve warm, with your favorite sauce and side dish. I especially love this with chimichurri sauce, but it also makes a great holiday meal with vegan gravy. I think this is best served warm right away, but you can store any leftovers in the fridge in an airtight container for up to 4 days.