Preheat the oven to 450 degrees F. Cut the cauliflower in half and remove the core and leaves. Roughly chop the cauliflower and place in the food processor. Pulse until the cauliflower is small and fine like rice.
Dump the cauliflower rice out onto a large rimmed baking sheet (If your baking sheet is average sized or small, use two.) Drizzle the olive oil over the top. Then mix with your hands and spread the cauliflower rice out into a thin layer. Sprinkle with salt.
Roast in the oven for 5 minutes. Then stir and smooth out again. Roast, another 5 minutes. Serve warm.
Sometimes I like to add a little curry, cumin, or chile powder to the cauliflower rice, depending on what main dish I'm serving it with.