Luke Mangan is best known as a celebrity chef. But behind thescenes, it is property that has ensured he can create the delicious food he serves.

At the age of 28, Mangan bought his first terrace in the Sydney suburb of Paddington. He sold it seven months later and used the $400,000 profit as seed capital for his first restaurant venture, Salt in Darlinghurst, Sydney.

Today, Mangan oversees a $100 million business empire across five countries with 19 restaurants and 700 staff. He also has a licence deal with Virgin Airlines and Carnival Cruise Lines, where his Salt Grill restaurants are on board five P&O cruise ships. Soon he will be cooking on Belmond’s Eastern and Oriental Express train from Singapore to Bangkok as well.

But it wasn’t always like this.

Mangan is a cautious businessman who believes in spreading the risk. His advice for anyone going into food, for instance, is: have other income streams.

“I started at 15 as a cooking apprentice in Melbourne. I did my hard slog, then headed to London and worked at the Waterside Inn with famous French chef Michel Roux,” says Mangan.

“I came back to Sydney when I was 25, worked at the CBD Restaurant in 1995 before opening my first restaurant at the age of 28.”

Now at the age of 45, Mangan says he is “in a good space’’. And admits his success is down to one of the oldest investments. “Property has been good to me. I’ve bought a few units off the plan, sold them and made good money. I still own three units in Sydney, which I rent out. Property is easy. It can sit there and be rented.’’ He says it is tough to make a goodliving from owning a restaurant.

“You have to create other income streams, so that if one fell over, another will help prop up the business.”

After closing Salt in Darlinghurst, he opened Glass Brasserie at Sydney’s Hilton Hotel in 2005. Just before the global financial crisis (GFC) in 2008, he opened a restaurant in San Francisco, but closed it within three months.

“It was an expensive affair, but I had no choice. The GFC then hit Australia and we felt it at Glass. Overnight, the corporate lunch market went dead.

“We had to come up with a different tack – come for glass of wine, a burger or a piece of fish and salad, all for only $18. We were inundated with secretaries and office workers who wanted a quick lunch at the bar.

“It became so packed that it spilt over to the main restaurant. The restaurant still has the same deal, but it now costs $25.”

In the face of the GFC, Mangan realised he had to have other income streams, so he started his Providore range including olive oil, spices and balsamic vinegar. He also managed to write five cook books.

The GFC also forced him to sell 50 per cent of the Salt brand to a Japanese partner, which helped him expand the brand to Asia.

Mangan does not employ a chief financial officer, but instead keeps a close eye on his finances. He has an accounting firm that has been with him for more than 20 years and makes sure he is on top of all the operations across five countries: Australia, Japan, Indonesia, the Maldives and Singapore.

“I am up at 6am. I go for a swim or run at Bondi Beach and am back at my desk looking at my emails by 7.30am until 12.30pm when I head for the city to oversee Glass.

“Every restaurant manager gives me a daily report on the revenue, how many covers were sold, what were the positives and negatives.

I want to know everything.’’

When he started as a chef, Mangan recalls thinking the restaurant business was all about the chef. Now he is older and wiser, he says it’s all about the customer and their experience.

“I realised by the time I was 35 that I did not want to be in the kitchen working 12 to 14 hours a day. I needed to get out of the kitchen and expand the business.’’

Beside his business and property, Mangan has a self-managed super fund with property and blue-chip shares as his main assets.

One of his worst investments was starting Baby Bites, an organic baby food venture that failed and he lost $500,000.

“It was a very expensive exercise, an experiment that did not work. But I had to move on.’’

And what advice would he give a youngster who wants to be a chef and run his own restaurant empire? “Don’t do it,” he says with a grin.