I am sitting at a sunny table on the balcony of the Ritz-Carlton Spa in Naples, watching chef Nathan Lingle teach us the seemingly impossible: How to make an entire meal that is tasty, healthy and totals less than 1,600 calories. Oh. and animal friendly as well.

I am very worried as I sit here, sipping Evian from my glass that a smiling waitress keeps refilling, because up on Chef Lingle's dark-wood counter I see tofu and cauliflower and udon, which, I soon learn, is a Japanese spaghetti-like noodle usually made from wheat. I am worried because I know, to be polite, I should eat everything set before me. After all, I am a guest of Gabby's. Gabrielle O'Boyle is her real name. She is my babysitter and escort while I am on Ritz property. She is from the public-relations department, and she is watching my pen because someone has probably told her I am prone to writing outrageous, untrue things, and I scribble illegibly so she cannot read my writing: Here's what I like: Gabby's rectangular glasses. Here's what I don't like: cauliflower and tofu.

Skeptical? Absolutely. I am a gourmand of ethnic, hole-in-the wall restaurants-Jamaican, Indian, American-Southern, Mexican and Cuban and French-where the cooks embrace those greasy, unctuous substances that can melt, rise to the top and magically congeal once again like ice on a pond. Give me tamales and biscuits with lard. I want eggs and butter in my hollandaise. I want cheese so fatty it appears to sweat when heated. As for any milk with the word "percent" in the name.throw it to the hogs.

But I dare not say these things to Chef Lingle, a man who grows his own micro greens and mushrooms at home. Lingle is a high-energy, young, smallish man-very lean-with a boy's face, and pink, healthy skin that looks as if he hasn't even yet begun to shave. (OK, OK, I'll give him this: He is a walking advertisement for spa cuisine; I will listen, open-minded. for a while.)

Lingle is showing us how to make a vegan meal, which means it is free of all animal products, even milk and eggs. That is why he has chosen to make his questionable mayonnaise with tofu and vegetable oil and vinegar. Lingle has a nifty little blender that he holds in his hand. It is skinny and white and plastic, with a little metal propeller on the end that he lowers into the bowl like an electric hand mixer, and before you know it he has whipped up a white sauce that looks exactly like mayonnaise. He stirs this into a mixture of cooked, cubed sweet potatoes, celery, capers, parsley, lemon zest and plum tomatoes. For garnish and flavor, he includes a dollop of balsamic vinegar mixed with pureéd prune baby food.

I am no fan of potato salad, but to my surprise, this orange version is delectable, both sweet and sour with a slight crunchiness from the capers and pieces of celery. Gabby and I gobble it up. She mentions that the Ritz-Carlton has a manners class for children, and I wonder why she has chosen this moment to share this with me. Gabby sets her fork upside-down on her empty plate. I hurry and do the same, and I wipe my mouth with my linen napkin to show that I do indeed have very good manners and that finishing school would be superfluous in my future.

It is time to make the entrée. Chef Lingle steams the cauliflower with onions and cloves of garlic, then sautés peas and shiitake mushrooms. Every time I try to sauté mushrooms at home, they sweat, creating a grayish, nauseating soup. The secret, he tells us, is to keep the heat at medium-high to sear the skin and trap the juices inside. Cheerfully, patiently, Lingle answers all of our questions, and boy, do we pepper him with queries. This is a chance, after all, to grill a chef at one of the highest-rated resort restaurants in the world.

Next, he uses his mixer to whip the now-softened cauliflower and onions and garlic into something that looks like runny mashed potatoes. I remain skeptical. He pours this over the udon noodles and vegetables, then tosses it with some salt and truffle oil, which is actually olive oil infused with essence of truffle.

It's expensive, but he lets us all sample a small spoonful. It is unlike anything I've tasted. a slight garlic, slight electric-current flavor as unique and distinct as guava. The other three people in the class, all of them Brits, coo between swallows, but we must remember these people come from a country where fresh, al dente vegetables are reserved for livestock. I'm not as enthusiastic as they are about the entrée but eat all of it because that's what Gabby does, and I do not want to be an ungracious guest. Please, water lady, I say inside my head. Please bring me some more Evian. And then, she is there. This is what I love about the Ritz-Carlton. I never want for anything very long at a Ritz-Carlton. I always scrutinize Ritz employees, searching for some hidden, surgically implanted antennae that detect human discomfort and desire.

As Chef Lingle cooks, I realize I have only one criticism of this cooking school: Like La-Z-Boy football viewing, there is no real participation, just observation. I want to hop up there and have him show me the most efficient way to chop an onion. I want to work that little blender, even though he tells us we can buy our own at Wal-Mart.

Still, I am accumulating all sorts of morsels of information in my notebook. Here's one: Chef Lingle swears there is truly no difference in taste between flat-leaf and curly-leaf parsley. Also: It is a good idea to serve pickled anything as hors d'oeuvres. Pickled treats cause the saliva to flow, acting as a bell that awakens the digestive system. Also: Always choose heirloom vegetables when possible. By heirloom, he means those that haven't been genetically altered. With detectable un-Ritz-like disapproval, Chef Lingle tells us how some scientists are working to inject a gene from the codfish into potatoes to keep them from freezing underground.

Finally, it is time for dessert, and this is a very good thing because I can still taste cauliflower in my mouth. Chef Lingle drops saggy rings of dough into a deep-fat fryer, and just when I am about to say, "Hey, this does not look like healthy spa cuisine to me," he pulls them out of the oil, and I can see why this isn't cheating. It is because these doughnuts are the littlest things I have ever seen. I would say they look more like brown Life Savers, but Gabby is watching, too, and she would say I am making things up. OK, they are the size of fried calamari.

On top of everyone's cute doughnut, Lingle drops a spoonful of fresh blueberries and raspberries he has soaked in maple syrup. After two nearly fat-free courses, I feel terribly guilty eating such a thing, and I catch myself looking around the room, subtly cowering, like someone who has just popped a Tic Tac at a Weight Watchers' meeting.

Too soon, they're gone. I am wanting more. Perhaps when Gabby turns around I will seize the moment and lick the syrup from my plate.

If you go:

the naturally nutritious cooking class is held Tuesdays through Saturdays from 10 a.m. to noon at the Ritz-Carlton Spa in Naples. For more information, call 598-3300. Food themes change with each class.