These days his family trust is the main shareholder of the private business known for its Snak Logs, Nut Bars, and baking goods such as nuts and dried fruit. Hall has built Tasti to an annual turnover of about $100 million with 250 staff in Te Atatu.
Hall attributes the success to a strong management team led by chief executive Bryce Howard and marketing director Adrian Cook.
The board has two external directors, Peter Guise, chairman of accountancy firm Staples Rodway, and John Ashby, a professional director who has headed several food firms.
Hall sees his own role as strategic. "I help set the direction and the vision," he says.
The New Zealand business, whose snack bars represent about 60 per cent of sales, has seen its market become more competitive in recent years.
"We were averaging 15 per cent growth a year for about 12 years."
Griffins, which owns the Nice & Natural brand, Bluebird Foods and Kellogg provide the competition.
Tasti has benefited from the fact that people are doing more baking.
Meanwhile, always looking for new food categories, three years ago it bought the Hastings-based Kaweka Foods, a manufacturer of "shelf stable" long-life meals.
"What appealed about Kaweka was the technology they were using to package their meals," says Hall.
"We have just expanded the range and launched a whole lot of meals under the Weight Watchers brand and sell this into Australia."
"Over 60 per cent of our products are exported, which is hugely satisfying for everybody, with all these export dollars that we are generating," he says. Australia is Tasti's biggest export market, and the bulk of exports are muesli bars.
As Tasti celebrates its 80th birthday, Hall, who joined the business in his mid-30s, remains committed to staying private. "Our succession plan is we have no intention to sell the business," says the father of three young girls.
"We have gone through business cycles where we have been offered a huge amount of money with double-digit multiples from just about every major private-equity company in Australasia. For a period before the recession, I would get a phone call every week."
As a private company, Tasti has the freedom to contribute to local ventures. Hall runs a private conservation trust and Tasti profits help support this.
Over the years about 50 staff have travelled with Hall to his forests in Hawkes Bay to help with the BNZ Operation Nest Egg Kiwi project.
"Since we started that about seven years ago, we have raised and released about 130 kiwi chicks," says Hall.
"The staff get involved, they love it. In terms of attracting and retaining staff that kiwi project is pretty unique."
Best business achievement
"The decision to become the best manufacturer of bars in the late 1990s. Before then Tasti used to manufacture a variety of products, but we were masters of nothing. It involved a huge capital investment in machinery and investing in the right people."
Top tip
"Don't get bogged down in the day-to-day business - focus on the big picture."