If you'd like to be one of the new-style dinner ladies, sign up for a course in Essex

Mrs Plum got it very wrong. When the boy asked her what was in the fish pie, she told him: "Fish. You know, that swim in the sea."

The little boy's face sank. Finding Nemo pie? How could Mrs Plum have been so cruel? "I'll have the jacket potato," he said.

"Not mentioning the creatures," says Sara Plum, is one of the lessons she's had to learn since giving up her job as a catering manager at British Sugar in Newark to become catering manager (aka head dinner-lady) at St Peter's Primary in Nottinghamshire.

Although jobs in school kitchens pay substantially less than general catering (the top job in a secondary school pays £15,000 a year)‚ she doesn't regret the pay cut. She finishes at 3.30pm, has the holidays to spend with her two young children, and enjoys the thanks of satisfied customers.

"It's a different world, working with children. You are well loved and popular, the little ones think you're brill, and you feel more than just a dinner lady. I can say it has changed my life."

St Peter's is where Jeannette Orrey, now the UK's most famous dinner-lady, quietly began the school food revolution. Tired of dishing up processed food in the name of "best value" - "What they really meant was 'cheapest'" - Orrey decided to bring back real food and real nutrition. With great success; in a year, she increased the number of children eating school dinners from 70 to 200.

For Plum, following Orrey was a privilege, and a challenge. Her job interview involved a cook-off between herself and another candidate. She had to make 96 portions of lasagne, and was assessed on cooking style, temperature control, presentation and, of course, taste. "It was terrifying!"

With her team, she cooks 175 to 195 lunches a day - three choices of veg, one main course, one vegetarian, and a choice of puddings. All the ingredients are sourced locally.

Orrey has gone on to become school-meals policy adviser for the Soil Association, which promotes organic food and farming in the UK. She published a book, The Dinner Lady (Bantam Press, £16.99), with more than 100 sure-fire recipes, and rejoiced as Jamie Oliver took the school dinner revolution into the headlines and Parliament.

Her latest project, officially opened by Oliver recently at High Laver Hall in Essex, is a training kitchen for dinner ladies. Courses cost £300, and classes are small, with a maximum of 16 students. "We need to re-ignite the skill still there in a lot of catering staff," Orrey says. "They can use their skills and feel valued. Then we'll see new people coming into the profession."

Working with Ashlyn's Organic Farm, the courses are aimed at those already working as dinner ladies, those who want to brush up their skills, and those who are thinking of trying out the career for the first time.

Before Jamie's School Dinners hit the screen, Greenwich council had 54 dinner-lady vacancies. A recruitment day drew almost 500, and the posts are all filled. On the menu in Orrey's training kitchen is everything from knife skills and book-keeping to food safety, kitchen management, cooking, and how to "market" change to pupils, parents and head teachers.

With the right aptitude, it's possible to get a job in a school kitchen without training; you'll be sent on courses as part of the job. "You need to have a passion for food, be caring, enjoy working with a team, and able to withstand the heat in the kitchen," Orrey says.

The local education authority is the first port of call. Jobs may also be advertised in local papers, and it's often worth contacting a school directly. "Dinner lady" is a not a term that rests easy with Kevin McKay, the chairman of the local authority caterers' association. "It conjures up the idea of lumpy custard and gravy. These women are professionals." Perhaps, but, as Orrey says: "The customers are the children, and that's what they call us. They won't ask to speak to the unit manager."

Plum couldn't agree more. "You have to take children with you, they are our customers." She has even joined the school's environmental club, where she helps the children to plant and tend their organic-vegetable garden.

So what is her culinary secret weapon? "Meatballs with vegetables disguised in a tomato sauce. The children love it, and you know that they are getting all the nutrition they need."