Finely chop the cauliflower until it resembles grains. You can do this very quickly in a food processor, by pulsing the cauliflower until done; be careful not to go too far).
Optional for non-raw version: lightly cook the cauliflower grains, either in the oven on a baking sheet or in a saute pan with olive oil.
In a large bowl, briefly whisk the olive oil, lemon zest and lemon juice together with a fork.
Add the cauliflower “grains” and all remaining ingredients and toss well.