Of all the ways to cook cauliflower, roasting is not only foolproof and failproof, it's by far the most delicious. Depending on how you slice it (literally) you can have fork tender florets in under 45 minutes. Roasted Cauliflower is great as-is, but also totally adaptable for bigger, bolder flavors that pair with a variety of cuisines.
Heat the oven to 425°F with a rack positioned in the bottom third. Line a baking sheet with parchment paper.
Divide the cauliflower into florets, then transfer to a large mixing bowl. Add the olive oil, salt, pepper, and optional seasonings (if using), then toss until the florets are evenly coated with oil and seasonings.
Roast 25-30 minutes for small florets (less than 1"), or 35-40 minutes for larger florets (about 2" florets). Remove the sheet from the oven once halfway through and flip the cauliflower to ensure even browning. The cauliflower is roasted once golden brown and the stems are tender; you should be able to insert the tip of a paring knife into the stem and meet little resistance.