Preheat the oven to 375ºF.
Cut cauliflower into florets that are all about the same size. Pat dry with a clean towel. Place in a bowl and drizzle with olive oil. Sprinkle with salt and toss well.
Arrange the florets in a single layer on rimmed baking sheet, making sure the florets are not touching. (If the pan is crowded, the cauliflower will steam instead of roasting up brown and crispy.)
Bake until starting to brown and tender all the way through. (Test by passing a knife through one of them.) This will take between 20 and 40 minutes, depending on the size of the florets and your oven.