In truth, though, the kitchen siren puts a lot of thought into Christmas. One of her 11 cookbooks is dedicated to Christmas, featuring recipes like chocolate Christmas pudding and marzipan cake. She also fronted her own TV Christmas cooking show: her influence was so huge that when she lauded the importance of goose fat as a Christmas ingredient in 2006, supermarket sales of goose fat doubled in the UK.
Before our interview, she posted a photo on Instagram of her "Ultimate Christmas Pudding'' recipe on "Stir Up Sunday'' - the traditional day for beginning the Christmas pud. When she returns to London, the best-selling author will be straight in her home kitchen to make hers. "I will be jetlagged when I make it," she sighs.
She talks about her upcoming New Zealand live show tour early next year but there is a ban on any "personal questions". Over the past five years, Lawson has had her share of boil-ups - a court case with her second husband, Charles Saatchi, followed by their bitter divorce; allegations of her drug use; and a fraud trial involving two assistants whom she says she treated like family.
The past is another country. Lawson likes to live in the present. When asked what she might give up for New Year's resolutions there's a sharp intake of breath down the phone from Sydney.
"I think that's a dismal way of looking at it. I think more about what I might add.
"I would never give up food, not in any shape or form. Absolutely not.
"I always tell myself to live more in the present. But cooking does that for me. One New Year's resolution would be to stop just having the ideas and to start doing some writing, which I enjoy.''
The pudding
For Lawson, Christmas gets underway when she has the pud sorted. She makes edible Christmas decorations to hang on the tree, a ritual she began when her two children (son Bruno is 22) were little. Lawson makes gingerbread dough and carves it into festive shapes: stars, bells and snowflakes. Her voice quietens. "I call them edible but I'm so horrible that when the children were little I used to put lots and lots of ground pepper in them, otherwise they wouldn't have stayed on the tree. They're only notionally edible.''
On Christmas Day, you might expect Lawson to be at the stove, serving her family a feast. This year, she will spend Christmas Eve celebrating with immediate family. On Christmas Day, she and her children will join friends at a friend's home. Invited guests will divvy up the food. Lawson will bring the glazed ham, the pud, and brandy butter.
"I love doing the cooking but I won't be in my own house. You can't impose yourself too much. We will be at my friend's house and she's a very good cook. Her son is a chef so we will do it all between us.''
She will also whip up three Christmas cakes for her home tins - a marzipan cake (her favourite); her chocolate fruitcake recipe, and a third, yet-to-be-decided cake, so she has something to serve visitors. "Christmas cake is always essential, as is Christmas pudding,'' she coos.
Christmas Day, and the build up to it, can be a pressure cooker time. "You're bringing two things together that people feel stressed about - family and food. I always advise people to invite someone who you don't know well enough to not behave badly in front of.''
Has she done that? She skirts the question, simply answering that her perfect Christmas Day is a "more the merrier'' approach. "I think it doesn't matter if someone has to sit on a stool or if the tables don't quite match. I think that's part of the joy of it.''
Lawson decided at a young age that she wasn't going to take Christmas Day too seriously. Daughter of the London socialite and heiress Vanessa Salmon, she watched her mother under stress prior to Christmas, nerves rattled from cooking and shopping too much.
Lawson has said she had a fractitious relationship with her mother. She tells Canvas: "My mother would burst into tears near Christmas … I was determined to not take things so far. I wanted to make things easier for myself. It was much harder then. In those days, shops closed so early and you had to get so much done in such a short time.''
Her upbringing was privileged, and she lived in exclusive London suburbs like Chelsea, Kensington, and Holland Park. However, Lawson remembers her childhood Christmases being simpler and more basic than they are today. "I'm always driving my children mad by saying things like, 'When we got stockings they had a few satsumas in them.' We'd get a pomegramate in our stockings. Christmas was much simpler. Foil-covered coins, that kind of thing.''
Her mother, who died of liver cancer when Lawson was just 25, taught her daughters how to cook. However, she didn't teach Lawson how to bake or how to make pudding. Her mother also didn't like to eat.
She did advise her daughter to cook both a ham and a turkey on Christmas Day to allow for leftovers, though. "It's a very Jewish thing to want to provide a big spread. I always cook for eight but make enough for 30,'' Lawson revealed in her biography.
The cookbooks
Two decades ago, Lawson published her first cookbook, How to Eat, encouraged by Diamond. A best seller, she hails it as a career highlight.
"Nothing ever compares to the first time you have a book to hold in your hands that you've written," she says. "That never fades. That's the thing I love, the connection I have with other people.''
That book and a following one, How to be a Domestic Goddess, launched her television career, and her TV show, Nigella Bites, which ran on Channel 4 from 1999 to 2001.
On the cover of her third cookbook, Nigella Bites, Lawson is photographed with eyes downcast, a piece of food poised between full, parted lips. Throughout her career, she has been criticised for serving up "food porn''. When Nigella Bites premiered in the United States, a New York Times critic said she was too flirtatious. "Lawson's sexy roundness mixed with her speed-demon technique makes cooking dinner with Nigella look like a prelude to an orgy."
In interviews, she said her style was "intimate'', not flirtatious.
With three million-plus cookbook sales so far, she says her cookbooks have served as markers of where she is at in her life. She talks about this in the video promoting her 2015 cookbook, Simply Nigella, saying: "For me, the recipe is a highly charged, autobiographical form… Here is where I am now. This is my food. This is what my life is tasting like now.''
When asked how the food scene has changed since she started out in 1998, she says: "In a way, I'm very happy to say that I don't have to busy myself too much with the culinary scene. I'm a home cook, and that's really what slightly motivated me to write about food. It's really been taken over by the professional. You know, you don't have to be qualified or have any particular skills to be able to cook.
"I would like to think that people understand that home cooking is different from restaurant cooking. The home cook has access to so many different ingredients and influences today. I think home cooking has changed. A lot of people think that home cooking is just what your mother and grandmother made but that's not true. Home cooking is anything that you cook at home, and it means venturing out, in a way.''
The fans
Social media has allowed her to connect with her fans in new ways, although her book readers outnumber those she meets through Facebook, Twitter and Instagram. She loves the two-way exchange with her fans, who send in photos of her dishes.
"I love to see what other people are doing with my recipes so it turns it more into a conversation - and that's what I like.''
It's part of the reason why she is bringing her live show, An Evening with NIgella Lawson, from the West End to Australasia: it is a chance for her to share her story about her life as a food writer; to talk about the importance of food and the part that food plays in our lives.
"Food sustains us. But it plays such an intense emotional part in our lives. It's part of the story of who we are and how we express ourselves. Food is a repository for memory. It's that whole other side of food that isn't just about the bare bones of it or the practical side of food.''
Less than a month from 2019, what does Lawson hope the New Year will bring?
"Do you know what?,'' she confides. "I'm not a planner. That's one of the reasons why I'm happy to have my [live show] so unstructured.''
She has two cookbooks on the burner. She will potter about in her kitchen and see what simmers. It seems surprising she doesn't have a publishing deadline, but she says: "I don't have anything absolutely fixed. All I know is that I have these ideas and I need some time to have a bit of a play. I'm not sure when or how they will become books.''
Her 59th birthday is just after the New Year, on January 6. How does she feel at this point in her life, in the last year of her 50s? "Do you know what? I'm not really a birthday person. I don't really reflect on that. I think I'm just lucky to be alive.''
"I think life always moves forward. When it stops doing that, you're dead. I think in a way that's what makes it exciting. You're constantly aflux.''
Nigella Live on Stage: Auckland, January 22; Wellington, January 23; Christchurch, January 25. For tickets to her show, go to nigellaliveonstage.com
