Established in 1988, the business entered the US market as an importer and distributor of New Zealand game meats, primarily venison, but, over the years, the product line was expanded to meet the demands of clients and customers.
Mr Mitchell's involvement with the deer industry dated back to his teenage years in Central Otago.
Originally from Ranfurly, he was educated at Otago Boys' High School and the University of Otago, although he quipped he was not at the latter for very long.
His parents were running a funeral business in Alexandra, in which he and his twin brother Peter were involved. When the twins bought a small 33ha property near Alexandra, there was not enough land to farm sheep and beef.
It was the late 1970s and the beginning of the farmed deer industry in New Zealand.
Relatives at Dipton with a deer farm suggested the brothers get into deer farming. They started fencing the property but could not get suitable posts so they obtained a line of tanalised posts being pulled out by the power board and cut them in half. They bought an old house from the Ministry of Works and turned it into a deer shed.
All the while, they were involved in the funeral business; one minute they could be on the farm, the next they could be picking up a body.
Mark and Peter went to Fiordland, where they trapped deer out of the bush on the south coast to be taken to farms.
To capture the animals, they fenced large areas of bush that were home to the broadleaf tree, a favourite of New Zealand deer, and the tree was used to bait the trap.
At 18, Mark declared if he ever had a business to do with venison, he would call it Broadleaf. The teenagers were paid in deer, which worked well as they wanted to increase numbers, and they bought 10 hinds from Dave Saxton for $500 each.
Their hind numbers increased to about 50 or 60 and prices quickly went from $500 to $2500.
Then their parents asked them if they wanted to be undertakers. Mark decided against such a career.
Plans to get a venison slaughter plant operating in Central Otago were scuppered as there were not enough deer but they knew of a plant being built near Tauranga.
So they sold the property in Alexandra and bought one handy to the plant, which was owned by a farmer co-operative.
But then interest rates soared to 18% and the 23-year-olds were paying $7000 a month, so they worked in the slaughter plant to earn money.
At night, they started making venison sausages in a butcher shop in Tauranga, finally getting the recipe good enough to eat.
They ended up selling to Woolworths, New World, and FoodTown, and, by selling some hinds, managed to buy a manufacturing butcher shop.
Sneaking some sausages into their bag for a trip to the US, they cooked them up at the National Restaurant Show in Chicago — the biggest food show in the US — where they were well received.
Broadleaf was set up in June, 1988, but it could not all be about sausages; they had to find out what customers wanted.
"We could have gone broke," Mr Mitchell said.
But Broadleaf did not "go broke" and the company now imported meat from Duncan New Zealand and Pamu Farms NZ (Landcorp), with venison, elk, lamb and AngusPure beef, along with Wagyu beef from Australia.It owned and operated a 56,000sq ft (5202sq m) distribution facility in Los Angeles that employed 80 people and sold to 400 wholesalers.
It had another facility in Texas, which employed 50 people, and that was a wild boar and bison facility that exported to Europe.
Duncan New Zealand, established in 1990 by Andy and Vinnie Duncan, supplies venison to customers around the world.
It owns and operates two purpose-built venison processing sites, one in the central North Island and the other opposite the Invermay research centre at Mosgiel.
Broadleaf had been working with Duncan NZ probably for more than 20 years and they had a good relationship, Mr Mitchell said.
The visit by eight of Broadleaf's "handpicked" wholesalers was a joint initiative by Duncan NZ, Broadleaf USA and Pamu Farms NZ.
For most, it was their first trip to New Zealand and they were impressed with the "clean, green" nature of farming, the care of the animals, and the passion of the farmers.
They had visited a Pamu property near Taupo, an AngusPure property near Taihape — American Angus genetics were coming to New Zealand from the US in the form of semen and embryos and that was a "real good story" — and met Landcorp chief executive Steven Carden.
The group dined at Wellington restaurant Logan Brown where they enjoyed a creme caramel made from deer milk, before heading south.
Late last week, they visited Pamu's Thornicroft Station near Lake Mahinerangi and Duncan New Zealand's plant.
That was followed by the weekend in Queenstown and Wanaka and then today
will be spent with Wilson Hellaby in Auckland looking at lamb and AngusPure, before the group flies back to the US tonight.
Mr and Mrs Mitchell were staying on for a few more days and were looking forward to spending Easter at Wanaka.
They deemed the trip very successful; the group came from Boston, Baltimore, Michigan, Missouri, Florida, Texas and California, so there was a good geographical spread. Some came from "huge" multi-unit businesses and others from smaller family businesses.
After they had seen farming systems in New Zealand, the intention was for them to become ambassadors, Mr Mitchell said.
Their customers wanted to know the story behind where their protein came from and the passion that had gone into producing it.
"We do a good job of telling that story," he said.
As demand for venison had been increasing, there was an expectation more would be charged for it and the Mitchells had taken that on board, as opposed to a lot of European customers that were fighting to bring the price down, he said.
They could see that if they were not prepared to pay more, the meat would "go somewhere else".
While he did not really follow other markets, as far as the US was concerned, he believed there was still a huge amount of potential for venison. It fitted in with the "millennials " and what they were after.
"It's got all the things the body's looking for," he said.
As far as the future, Mr Mitchell said the company would continue to grow and they were still seeing new opportunities.
While he had no plans for retirement, he said the couple might eventually return to New Zealand, possibly for several months a year.
They came home for a "New Zealand fix" a couple of times a year, Mrs Mitchell said.
Mr Mitchell acknowledged it had very much been a team effort with his wife. The couple left New Zealand with 3-year-old son Tim, and 18-month-old daughter Kate to start the venture.
Mrs Mitchell started helping with the accounting side of the business. Otherwise, she would never have got to see her husband, she said, as he was working 20-hour days, and her role in the business just evolved. She particularly enjoyed getting out on farms and meeting farmers.
