Pull the leaves off the cauliflower and cut out the core in a kind of cone-shaped section. Break or cut the florets into small, regular pieces (about 1 1/2 inch) and put them in the steamer insert. Bring about 1 inch of water to a boil in the steamer pot, add the insert, cover, and cook for about 20 minutes, or until you can poke a paring knife into the stems and you can feel that there's still a little texture there.