Place cauliflower florets (about ¾ of head) in a food processor and pulse until they are close to the size of rice grains.
Transfer cauliflower to a microwaveable bowl; add olive oil and a pinch of salt and pepper. Microwave on high (covered) for 3 minutes. Let cool. (Pre-packaged bags of steamable cauliflower will work too.)
Divide cooled cauliflower onto 2 plates and top with divided amounts of greens, tomatoes, onions, feta cheese, olives and salt/pepper.
Pour desired amount of dressing on each; add croutons.