There's no doubt it's a vegetable. (Definitely not an animal or mineral.)
Just like most other food questions, this one has a ton of answers. For example, in his latest book Fast Food Genocide, Dr. Joel Fuhrman makes a strong case that you're better off skipping options like this one. (This snip is from page 55, and he means it. This guy is TOUGH!)
When you're building your own box lunch lifestyle, you make the rules. If you want to make your own breaded cauliflower and fry it for a weekday lunch, rock on. You'll learn pretty quickly if this is a good or sustainable vegetable option for you. Or it may be the right option for you TODAY because your kids want to try doing it themselves.
What about fried cauliflower gives you energy?
You, Box Lunch Boss, are in pursuit of a lifestyle--food and action--that helps you live up to your potential. Decide for yourself how to answer this question.
P.S. You can bake cauliflower, too. Just sayin'.