"The same cut can be used on a lot of different veggies," Hertzmann advises.
Hertzmann shows his students various techniques of cutting onions, carrots and other vegetables. When money allows, he also demonstrates butchering techniques with meat. The class is an introduction to basic concepts of knife skills, where he shows students how to hold a knife, how to hold the food and how to cut.
Students absorb a variety of tips for more effective knifework, including cutting the onion in half and peeling it first, and they learn how to make sure the knife is properly sharp for best results. They're hoping the skills pay off in future employment in food service, perhaps with restaurants or catering companies.
The classes contain a mix of students, including some from the San Mateo County Jail's minimum-security transitional facility, who are at the JobTrain nonprofit as part of the jail's work-furlough program. Students make two meals a day, breakfast and lunch, and also learn life skills, such as how to dress for a job interview.
Hertzmann started teaching the class in 2007 after he wrote the book "Knife Skills Illustrated: A User's Manual." He has also written and illustrated his e-zine "a la carte," which focuses on French cooking, since 1999. Hertzmann saw a photo of Adam Weiner, an instructor at JobTrain, and got inspired to join the effort. He emailed Weiner and before he knew it, he was walking in the door to teach his first four students.
"The program deals with the disadvantaged," he said. "There are a lot of people who have never been exposed to this."
In 2011, Hertzmann also started teaching at the county jail, which has a relationship with JobTrain and Weiner. While jail administrators at first worried about him teaching students with sharp objects, Hertzmann said he isn't concerned about the students because he knows how to use a knife. "I'm aware of what's going on," he said. "I can tell whether people are chopping or slicing just by listening." One of his female students was actually afraid of the knives at first, he added.
It is rewarding to him when he sees progress, something he experienced with the women he taught last summer who volunteered to stay week after week. One of his classes was particularly small, and he was also asked to teach fractions and ratios for baking, which he said is also useful for different aspects of life in general.
Hertzmann has been teaching on and off for many years. Until 2012, he worked at Sur La Table, where he taught self-designed classes in his specialties: Chinese, Japanese and French cooking.
"Cooking is a very relaxing thing," he said. It's also a social thing: He enjoys spending time with other people while cooking, and making many small dishes for parties.
Hertzmann learned some of his knife skills from other chefs, including picking up tips from Martin Yan for finely dicing onions. Some he came up with on his own.
He has taught knife-skills classes in cities including Vancouver, Toronto and New York City. He's also conducted multi-hour knife-skills demonstrations at places such as the Exploratorium in San Francisco and at events such as the Eat Real Fest in Oakland.
When he taught basic knife-skills classes at Sur la Table, the class size was usually 16 people and he would demonstrate to students for them to repeat. He's also occasionally led a class about breaking down chickens and butchering supermarket meat, and been invited by restaurants to work with cooks on their skills.
Student Adrian Perkins came to JobTrain to do research on unemployment, and ended up seeing documents about the class. He has been in the class since January. He didn't have much previous experience in cooking or cutting, but since taking the class, he takes more pride in his cuts and how they can make the overall meal look better.
"He's very precise on teaching," he said of his teacher. "He can be walking through and say, 'That's how I taught,' or, 'That's not how I taught you.'"
How food is affected by knife skills and how it ends up tasting is something Hertzmann said is important to learn. Once students understand general concepts, they might not need to follow recipes as closely and can use these skills all across cooking.
"My goal in life is not only to teach people how to cook, but also to learn principles to use in other things," he said.
Info: To read Peter Hertzmann's blog and book, go to hertzmann.com. Information about culinary-arts classes at JobTrain is at www.jobtrainworks.org.