MIKKEL KARSTAD HAS done time at Michelin-starred restaurants in London and at Copenhagen’s famed Noma — sometimes said to be the best restaurant in the world. He was head chef of the parliament in his native Denmark, and pioneered the New Nordic Cuisine movement, which elevates simple, seasonal, and wild ingredients to the fine-dining sphere. But he defines ambition expansively: “I had an early ambition to have a big family, at least three kids, and my wife Camilla and I met when we were really young.” The couple has been together for 24 years and shares four children.

Karstad’s interest in food also started when he was young, during holidays with his family on the southern Danish island of Tåsinge, where he fished with his uncles, and helped pull the vegetables out of the garden ground, washing and preparing them. As a child, he had trouble paying attention or sitting still, but at 16 he started restaurant work and discovered a knack.

I had expected his kitchen origin story to involve the first taste of some knotted and black currant–dotted baked good, a Danish answer to the madeleine, but he sounds almost sheepish as he explains the truth. “People told me I was good at it, and when I was in school I was used to the teacher telling me what I was not good at.” His proficiency bloomed into a career: “For many years, working in kitchens and restaurants, I loved it. Being part of a team and making a meal for a guest, and having them be pleased with it, and coming back again. Instead of sitting in a chair, getting to work with my hands.”

As he and Camilla grew their family, Karstad found that his culinary and fatherly ambitions were often in conflict. “I worked really hard for a lot of years,” he says. “To work as a chef at a high level, it’s a lot of hours, mostly evenings and weekends.” When his second child was born [Alma, now 16], Karstad realized his work was impinging on their family life. “Camilla was home alone too much with the kids.” He had to find a way to work with food in a more sustainable way.

As we talked, he was busily preparing for a private party the following day, an 80-guest fête for a couple’s 25th wedding anniversary. His day had started, as it does five or six times a week, with a before-sunrise ocean swim. It was October, the water under 50 degrees, and Karstad could sense the coming seasonal change, the air clean and getting colder. “Good weather for mussel and seaweed harvesting,” he tells me. In warm, dusty summer, the water is too hot for seaweed, and after the frost sets in it is locked beneath the surface. “The water right now is crystal clear, but not so cold you can’t swim in it for quite a while. If you swim all year round, your body gets used to it, and it’s quite special to go down to the cold water in complete darkness.”

After the swim comes a simple weekday breakfast with the kids still living at home. Fruit (they try for what’s in season and grown nearby), yogurt, and granola. The recipe can be found in “Nordic Family Kitchen” and involves sesame seeds, honey, and olive oil. Camilla makes it in big batches that last the family a couple weeks. On the weekends, breakfast is a more elaborate affair — they bake buns, fry an egg. In the book, Karstad calls for an egg to be drizzled with olive oil and accompanied by fried rapeseed flowers, or put atop fried bread with wild mushrooms. He also includes recipes for strawberry s’mores, seaweed flatbread, and fermented radishes with garlic flowers.

If all of this has the suspicious whiff of pie in the sky — like the latest lovely but impractical parenting advice from a Western European country with ample paternity leave and free childcare — Karstad can strike a winningly practical and forthright tone: “My kids have had periods, my oldest and youngest especially, where they were really picky. Now my oldest is a young man [Oscar, 22], and he’s very good at cooking food and he eats everything. But when he was 6, we called him the spaghetti and ketchup boy.” In the book’s foreword, Karstad admits that his children have occasionally found his wild culinary adventuring demanding, but when it comes to their food education, he takes the long view. “If I have a rule, it’s that you should always taste it. If you don’t like it, it’s okay; you don’t have to eat it. Taste buds change all the time as you grow up. Really small children sometimes eat anchovies and olives. Then a few years later, it’s too salty and strange. And then it changes again. For Camilla and me, it is important just to be curious.”

If kids take part in finding the ingredients, Karstad says, whether from a walk in the woods or a trip to the farmers’ market, then they get more excited to try the food. He points out that kids usually like pasta, so it’s a good vehicle for them to try new flavors. At least once every two weeks, he makes the pasta carbonara recipe that appears in his latest book. “It takes me maybe 15 minutes, and everybody loves it.” It’s not especially Nordic, he allows. “But you can make the pasta yourself, and use nice local bacon and local eggs, and then it’s as close to local as you can get. And though pasta is Italian, it’s also one of the most common things to eat all over the world.”

After I mentioned this to my partner, an Italian New Jersey boy, he opened Karstad’s book and made the Nordic version of the dish for our breakfast. Our 4-year-old daughter whined about her bacon not being served in crispy diner-style strips. “Just have a taste,” we told her, and a little while later she asked for seconds, and then we all went for a walk in the woods.

World traveling and cultural exchange have also been crucial to Karstad and his family’s culinary education, their appreciation for food and its interpersonal significance. “You learn so much from meeting people in their own country and eating together with them.” And yet the Karstad children retain a taste for home. When the family traveled to Vietnam for Christmas and New Year’s a few years back, they loved the food but bemoaned the absence of their traditional holiday feast. “The first thing they mentioned was not, are we going to get presents, but what are we going to eat for Christmas. The kids love the tree and the presents, but the food is what they really talk about.”

This Christmas, Karstad and his wife’s extended families will come together for the holiday. “I do all the food, but I do it like my mom did, and my grandmother did. Duck with apples and prunes inside, roasted pork with pork cracklings on top. I score the skin of the pork and put salt on it so that it gets really crispy, and then fry it in the oven. Potatoes browned in sugar and butter. Normal white potatoes, pickled red cabbage, and a thick brown sauce made of juices of the pork and the duck. For dessert, we have risalamande (cold rice pudding) that we eat with warm cherry sauce. Very traditional Danish Christmas food. It hasn’t changed for many, many years.”