Place 1 1/2 cups water into a saucepan or pot. If using a steamer basket without a handle, add it to the pot now: the water surface should be right under the basket. Bring the water to a boil.
Once boiling, add the cauliflower (in the steamer basket, if it has a handle). Steam with the lid on 10 to 12 minutes until just tender, testing with a fork to assess whether it’s done.
Carefully remove the cauliflower to a bowl, draining any excess liquid. Toss with the remaining ingredients and serve. (Store leftovers refrigerated.)