Thornton's task over the summer was to learn as much as she could about cheese-making and research the market for ingredient and equipment kits aimed at the home cheese-maker.
Her temporary job turned permanent when she was charged with developing and launching a range of cheese-making kits.
She completed cheese-making courses, tested recipes, wrote up instructions, sourced ingredients and equipment and roped in family and friends to test prototype kits.
The Mad Millie name is a nod to Eastwood's elderly aunt who had an obsession with homemade food and organics well before they became trendy.
Thornton's research revealed that a major issue for anyone trying to make cheese at home is often not the technical side, but obtaining ingredients and equipment, as suppliers sell vital ingredients, such as cultures and rennet, in commercial quantities.
Before launching Mad Millie, Thornton says it had never crossed her mind to make cheese from scratch at home.
"Because I had no idea about cheese-making when I was developing all the kits I came from quite a good standpoint because I was doing as most people would be doing it who used the kits as a beginner."
The initial launch of 200 kits sold out so fast that imake was left scrambling to reorder the components.
The kits are assembled in New Zealand with the various items coming from around the world: plasticware and thermometers from China, moulds from Italy, cultures from Europe and rennet from New Zealand.
Mad Millie celebrates its second anniversary this month, having sold 55,000 kits since launch.
Turnover in the past financial year was $1.5 million and Thornton expects that in a couple of years sales of Mad Millie products will make up 20 per cent of imake's total revenue.
In time, the DIY food kits, which retail for between $40 and $180, will result in the Mad Millie range dominating the company's sales figures, says Thornton.
She says the initial idea with Mad Millie was to provide a more female-focused product to balance the existing range of homebrew beer, wine and spirits products sold by imake, but there has been just as much interest among men.
Customers fall into three broad groups, says Thornton: foodies who love to experiment with recipes; rural lifestylers; and DIYers who are already making their own homebrew or wine.
Every recipe comes with online YouTube instruction and there's also a company helpline. Customers also turn to Mad Millie on Facebook and Twitter for answers to cheese-making dilemmas or just to show off their creations.
The Mad Millie range has now grown to include preserving kits and a just-launched sausage-making kit.
Also growing is the number of countries in which the Mad Millie kits are available. Australia, where imake already has a warehouse, was a natural extension for the Mad Millie brand, and Thornton is aiming to export to North America and Britain in the near future.
She says a push into the US will focus on the gift market, with a single, beautifully boxed kit, which she will show at a gift fair in Chicago next March.
"There are a few competitors in the US but they aren't very well marketed, they're very small scale and the presentation isn't great and we just feel we could do a lot better at it."
Now she is imake's marketing manager, all this product development and growth leaves little time for Thornton to do much cheese-making herself, although when she does it's to turn out some hand-stretched mozzarella.
"It's been my project, but all the way I have had Peter to mentor me, so it has been an amazing learning experience."
