This is the BBC.

In this edition of the Bottom Line, we're looking at the restaurant sector and what makes a restaurant business successful.

Hello and welcome to the bottom line. Back in the day, the preparation of food was not something we left to business.

We tended to cook for ourselves,

except maybe on special occasions or trips away. But over the last three decades, casual dining

outside the home has become hugely more popular. Restaurants have taken over from some home

cooking for time-poor households, and they've replaced the shops dying in some of our high streets.

So today we'll look at how the economics of the restaurant sector work, the more casual end in particular, the pizza express end.

What makes some restaurants work and others not, why so many chains rather than independence?

And why is Italian cuisine so popular? Food is the most important of our subsistence needs. Can we get to understand how capitalism

is running so much of it? Well, joining me are three guests who are involved in restaurants

in different ways, an entrepreneur, an investor, and one of the

country's top chefs, and first, the entrepreneur, Sarah Willingham. And your first job, Sarah,

it's not going back to your teens here, but your first professional job, Planet Hollywood?

Yes, first professional of all was Planet Hollywood. I started working in restaurants when I was

13 and just found out it was a really good way of getting extra cash.

I was never without a pound in my pocket through the tip system, which was great back in the day.

And then I purely by chance really fell into doing it, I would say professionally, like as a career.

I'd always thought it was just going to be a way of earning a bit of extra cash. Then I had a part-time job and was working at the frog and roast beef in Paris.

As you do. As you do. And the people who were opening Planet Hollywood at the time were also the guys that had opened the frog and rose beef. And the people who were opening Planet Hollywood at the time were also the guys that had opened the frog and roast beef.

And they told the owners that they were having an absolute nightmare with the Americans and the French.

They just could not communicate at all.

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