Vegans don’t eat cheese, milk, eggs, meat, fish or seafood, or any other product that comes from an animal. Given the constraints, is it even possible for a vegan to serve as a chef in a non-vegan restaurant? Apparently, yes.

I tracked down and spoke with three vegan chefs who are working in Portland to ask them how they manage it. (A fourth who was on extended holiday in London eluded me.) Among the challenges they face: Needing to taste animal products before they send dishes out of their kitchens, career limitations and the contradictions between strongly held personal beliefs and professional ambitions.

A lifelong vegan, Mark “Wiz” Czemerys didn’t set out to be a chef. And certainly not a chef in a non-vegan restaurant. But after he was laid off from a desk job during the recession, spent time touring the country playing in a punk rock band and then returned to Maine looking for a job, he happened to meet a kitchen manager who was hiring. The kitchen manager offered to interview him.

“I went in, and here I am six years later,” Czemerys said, describing how he landed his job at Silly’s in Portland’s East End.

Meanwhile, at David’s Opus Ten in Portland’s Monument Square, there is actually a specific position for a “vegetarian chef de cuisine,” who is responsible for that restaurant-within-a-restaurant’s vegan tasting menu, as well as the vegan and vegetarian dishes on the larger David’s menu. Vegan Rocky Hunter holds the job. He is expected to help where needed in the busy kitchen, which means he also prepares non-vegetarian dishes.

In Hunter’s experience, vegan chefs are more prevalent in other parts of the country. After culinary school, Hunter worked in Denver and Portland, Oregon; the latter is a famously vegan-friendly city.

“When I moved to Maine, I was a pretty rare bird,” he said, adding that here it’s more common to find vegan chefs in casual restaurants than in fine-dining establishments such as Opus Ten.

“I’ve always been up-front about (being vegan),” Hunter said. When he interviews for jobs, “I say, ‘Look, treat it like a food allergy.’ It might be a deal breaker for some (restaurants), but I’ve done pretty well.”

Silly’s chef Mark “Wiz” Czemerys cooks housemade tempeh sausage, which is an ingredient in many of the restaurant’s breakfast dishes.

His resume includes stints at Silly’s and Local Sprouts Cooperative Cafe. Unsurprisingly, local restaurants with vegan-friendly menus – including both Silly’s and Local Sprouts – are where I found Portland’s vegan chefs.

Although Czemerys is the only vegan staff member at Silly’s now, the restaurant has had others in the past, he said: “Vegans do gravitate toward working there.”

But even at a vegan-friendly establishment like Silly’s, vegan cooks need to eat animal products.

“At most restaurants, if you’re sending out food, they want you to taste it,” explained chef and vegan Cady Frazier, who has worked in a number of Portland kitchens, both vegan and non. “It’s one of those things that’s part of the job,” she said. These days, Frazier is chef at the Catherine Morrill Day Nursery in Portland.

Since Portland has only a handful of entirely vegan restaurants, vegan cooks in the city face a tough choice, Frazier said: “You either need to choose if you’re a vegan or a chef, as far as work goes.”

Frazier has chosen chef, but she brings a distinct vegetarian flair to her job. Each week, the Catherine Morrill menu includes all-vegetarian breakfasts and snacks and two or three vegetarian lunches, such as lasagna with butternut squash and spinach, homemade baked beans, falafel and lentil vegetable soup.

“Vegan isn’t really possible because of the USDA guidelines and funding,” Frazier said. “All of my soups are vegan, but I serve them with a cheese stick or with shredded cheddar cheese on top to count as a USDA protein.”

She uses less meat than is standard, substituting black beans for part of the ground beef in taco filling and swapping lentils for half of the ground beef in her sloppy Joes. “I try to make the meat dishes a little less meat-centric,” she said.

Frazier samples all her dishes.

“I do taste meat and dairy,” said Frazier, who described a taste as “a tiny bite.” “I’m working with kids, and I don’t want to risk sending out a meal that is no good.”

When she worked in a bakery, the need to taste every batch wasn’t as necessary, she said. She’d taste “the recipe the first couple times until I had a solid understanding” of it and after that she relied more on “smell and color” for quality control.

Hunter, at Opus Ten, says that to minimize the amount of meat and dairy he needs to taste, he often prepares food differently than a chef who eats meat might.

For instance, when making a sauce or a soup, he will keep it vegetable-based until the very end when he adds in the butter or beef stock. He also relies on the taste buds of meat-eaters.

“I have a team of (meat-eating) co-workers I trust a lot,” said Hunter. “I’ll ask them, ‘What do you think? Too acidic? Too salty?’ ”

But that only goes so far.

“When I make a meat-based dish for someone, I want it to be excellent,” Hunter said. “I’m definitely tasting it.”

Silly’s owner Colleen Kelly, who built her busy restaurant in large part by catering to vegans, vegetarians and those seeking dairy-free and other non-mainstream foods, said she is proud to have a vegan chef in her kitchen. Yet she admits the job presents extra challenges for vegans.

Speaking of Czemerys, Kelly noted that “the first time he cracked an egg was on my line.”

While many vegans would recoil at the idea of working with animal products, Czemerys said he doesn’t dwell on it, preferring to focus on his contributions to producing tasty, plant-based dishes.

“A lot of people say, ‘You’re vegan. How do you work in a place that isn’t completely vegan?’ ” Czemerys said. He responds to such questions by pointing out “it’s impossible” for anyone to be 100-percent vegan in a “society that isn’t vegan.”

“If I go to Whole Foods and buy vegan food, I’m still purchasing from a company that sells meat,” Czemerys continued, adding, “I can’t change the world, but I can change my world.”

Still, the day-to-day work life of vegan chefs at non-vegan restaurants is filled with tasks that would be difficult for your average vegetarian.

“I work with meat and dairy every day,” Hunter said. “Yesterday, I went upstairs and butchered sirloin for a couple hours. It’s something I think about a lot in my personal life.”

Frazier, too, has been forced to reflect on the contradiction between her personal beliefs and the requirements of her profession. Like Hunter and Czemerys, Frazier is vegan for ethical reasons.

In wrestling with the tensions inherent between her work and her beliefs, Frazier said she justifies having to taste meat and dairy on the job by realizing that her doing so doesn’t add to overall animal suffering or pollution, “because I’m tasting food that will get sent out anyways.”

Perhaps counterintuitively, Frazier, Czemerys and Hunter say their work allows them to feed more vegetarian food to more people. For instance, Opus Ten recently switched from offering a vegetarian tasting menu to offering a vegan one.

“All the meat stuff is kind of a means to an end,” Hunter said. “It’s what allows me to entice people onto the path of veganism with phenomenal vegan food.”

Avery Yale Kamila is a freelance food writer who lives in Portland. She can be reached at avery.kamila@gmail.com, Twitter: AveryYaleKamila