Wahaca warming the Wharf chili-style

Mark said: "The response from the Canary Wharf public has been excellent. The first few weeks were very busy indeed and although it's levelled off a bit now it's still going very well.

"We had the usual issues faced by any new restaurant, such as how to deal with 150 people all turning up for lunch at noon. That doesn't happen at our Covent Garden and White City restaurants - it's a particular Canary Wharf thing, as it's people with lunch hours rather than shoppers who kind of drift in.

"But we think we've overcome any problems and the response we've had has been very positive indeed."

Thomasina and Mark have plenty of ideas to keep Wharfers coming back to the Park Pavilion outlet for more in 2010, as Mark explained.

He said: "We're launching a takeaway service in mid-March because we know not everyone has time to come in and sit down for lunch. It will just be burritos to start with, but if it takes off we'll start doing other things like soups and salads.

"We had a test run last Sunday, when we invited some bloggers down to see how we could cope with the demand and the feedback was very positive."

Before then Wahaca will open its newest attraction, a terrace bar overlooking Canada Park. Thomasina feels it will be perfect for customers looking for something a bit different on a night out.

She said: "The bar will open in the next two or three weeks and we're really pleased with it. We've got heaters in there, although but it's been so cold we might have to put some more in.

"But it will really come into its own in the summer because the views across the park are fantastic. It's very exciting - Mark and I might even work the bar on the opening night because we like it so much."

Former Masterchef winner Thomasina has also written her first cookbook, Mexican Food Made Simple, to be published in March.

She said: "It was fun to do and hopefully people will like it. I can't think of any other British Mexican cookbooks out there and I've tried to make it accessible to everyone. There are simple recipes right through to more complicated ones but it's main aim is to get people to buy things from the supermarket and experiment at home.

"Mexican food seems to have caught the imagination here and hopefully this will give people the taste for it even more."