Butterfield Market, Whole Foods, Guido's and other specialty produce markets are carrying this funky looking vegetable and when you stop by, choose one just as you would a usual broccoli or cauliflower - firm, no brown spots, well in tact. Once you get it home, it is hearty so it can last a while in the fridge while you decide how to enjoy it.
To prepare it, you could certainly chop it and eat it raw or with your favorite salad dressing or vegan dip.
You could also steam it, and then pop it into a quick stir- fry.
You could roast it in a bit of olive oil with olives and capers.
You could make a cauliflower-leek soup, according to any typical recipe - just warn your guests before you serve it not to be fooled by the color!