Equipped with annotated maps and guided by a fascination with ethnic food, the Tilson family goes on an idiosyncratic tour of the Sydney suburbs.

I'm ready for Sydney, seafood field guide ordered and oven thermometer packed. My wife, Jeff (Jennifer), has bought us a spare suitcase in which to bring back our culinary discoveries, and online our 11-year-old daughter, Hannah, has found a promising shop called Hannah's Pies. After a flurry of e-mails to friends and several hours of Internet research, I've produced some heavily annotated food maps of Sydney, on which I've drawn walking routes and highlighted potential attractions.

We're a family accustomed to culinary adventures. I describe some of them in my new cookbook, A Tale of 12 Kitchens, which recounts our travels to 12 cities around the world and includes collages made with items (menus, photos, scribbled recipes) we collected along the way. Sydney could well become kitchen number 13. Our month in Australia, which includes two weeks in Sydney, has been prompted by an exhibition of my wife's ceramics that coincides perfectly with the launch of my cookbook there.

Sydney's cultural diversity should suit us. My parents live half the year in Italy, giving our home cooking an Italian bias, and Jeff's family runs a farm in Scotland. And our London neighborhood, Peckham, has the broadest range of international cuisines I've seen anywhere. Everywhere we travel, we love to explore ethnic restaurants and food shops, talk to store owners and try out local recipes. Staying in houses that have kitchens helps us feel instantly at home when we travel.

For our Sydney stay, we've been offered a generous loan of a fisherman's weatherboard cottage on Watsons Bay on South Head, where the ocean meets Sydney Harbor. At the airport, we clear passport control and quarantine with only Scottish oatcakes to declare. It's too late to visit the famed Sydney Fish Market or an organic farmers' market, but on our way to the cottage we spot a large Woolworths, which in Australia is primarily a grocery store. Hidden among the global foodstuffs are some Australian specialties such as Lamingtons, small chocolate-and-coconut-dipped sponge cakes named after Baron Lamington, governor of Queensland in the late 19th century. We also find Arnott's biscuits, Keen's mustard, Cherry Ripe chocolate bars, firm blocks of cottage cheese from New South Wales, kangaroo steaks, lamb sausages, Turkish flat bread and irregular bricks of halloumi, a mildly salty cheese. Jet-lagged, we stumble back to our idyllic cottage and its bright, wood-paneled kitchen, and prepare dinner as best we can. I experiment with kangaroo steaks, which I marinate in tamarind puree and cook on a griddle. Emergency backup for Jeff and Hannah are the lamb sausages wrapped in pita with halloumi cooked in balsamic vinegar. The steaks taste terrific, but we eat the sausages, too.

Sydney, as widely noted, is full of incredible food and architecture and exceptionally friendly people—but the city is surrounded by a dark, brooding natural environment that reveals itself gradually. In the morning, after the noisy possums have stopped their nocturnal antics, we're woken by an unearthly chorus of birds—lorikeets, sulphur-crested cockatoos, silver gulls—screeching, whooping, chattering and squawking. Crimson rosellas masquerade behind the ruby-red flowers of the stark, bare flame trees. Majestic Moreton Bay fig trees billow like sailcloth in the cold wet wind, their buttress roots rising out of a parkland streaked with rain. It seems as if the entire metropolis could revert to primeval jungle at any moment.

How apt it is that the most famous figure in Australia's colonial history is a captain named Cook. The country has what may be the world's most vibrant and spontaneous fusion cuisine, merging Asian, Middle Eastern and European traditions with Pacific Rim ingredients. The Asian influence has been perhaps the most crucial: Without provisions received from the East during Australia's first 40 years as a British colony (roughly 1788 to 1828), the European settlers wouldn't have survived. But it wasn't until after World War II that Australia began to shake off the British working-class food it had endured for decades in favor of a cuisine reflecting its ethnic diversity.

Nowadays, looking at a gastronomic map of Sydney is somewhat like viewing Australia's Great Barrier Reef from a helicopter: Hundreds of small reefs become immediately visible, each with its own distinct character. The multitudes of ethnic neighborhoods in Sydney are found mainly out in the suburbs—or 'burbs as Sydneysiders usually call them—and they are my main interest.

Our Australian friends are rather bemused by our choice of tourist activity. It's as if, on our first trip to New York City, we were to tell our friends there that we were planning to undertake a historic tour of bakeries in Queens—which actually sounds rather exciting.

The suburbs we visit on our first day are five miles west of the Central Sydney area. Jeff, Hannah and I cross the blue waters of Port Jackson on a ferry to Circular Quay to catch a CityRail double-decker commuter train out toward Ashfield. Although Ashfield is known locally as Little Shanghai, today I'm looking for a Swiss butcher who'd been recommended to us. We walk past shops with Victorian facades and awnings that block the fierce sun like a wide-brimmed hat. Sadly we find the Swiss butcher has recently closed, but we discover plenty of excellent Chinese and Indian food stores. Hannah spots some pristine bok choy and duck eggs, while I buy garlic stems, Chinese eggplant and squash. Later, when I'm cooking dinner back at the cottage, I'll sauté the eggplant and squash in olive oil and coconut milk and spike the dish with coriander and red chiles, to create a Thai-style curry.

A short cab ride east takes us to the residential hills of Haberfield, where we break for lunch at a pizzeria called Napoli in Bocca. The pizza we order is topped with prosciutto, basil and Parmesan and wood-fired to perfection. Then we root around in the friendly Italian deli where we buy Australian-produced tagliatelle. We also sample the local cannoli at Pasticceria Papa. They're extremely tasty, but we've been rather spoiled for cannoli, since we'd recently tried the fresh cannoli made by the owner of Manganaros in New York City. Hannah says her favorites are the exquisite ones we ate at Pasticceria Tolleta in Venice.

While Jeff installs her exhibition at the Liverpool Street Gallery the next day, I venture west alone, traveling 11 miles by train in search of Lebanese food in the suburbs of Bankstown and Lakemba. I'm particularly interested in tracking down a dessert called znood-al-sit, or Ladies Arm. After passing many Asian markets in Bankstown, I spy a pastry shop on Chapel Road South called Chehade El Bahsa & Sons, where I buy a freshly cooked znood-al-sit. Outside on the cold street I unwrap the beautiful green-and-red paper bag, take out what looks like a spring roll and bite into it. I almost fall over with delight. The warm confection is made with phyllo pastry rolls stuffed with clotted cream, deep-fried and sprinkled with pistachio flakes. I have to share these with Jeff and Hannah, so I buy six more to take home.

We need something for supper that night, so I volunteer to hunt for indigenous seafood at the Sydney Fish Market. Although the surroundings may lack the mercantile charm of other great fish markets, the seafood on offer is spectacular. I choose a dozen large banana shrimp, a barramundi fillet and a Balmain bug (a type of lobster). With such fresh ingredients, all that's needed is the lightest pan-frying in a touch of olive oil, plus lemon wedges and a sprinkling of finely chopped flat-leaf parsley. Before leaving the market, I have a mixed seafood plate for lunch at a wonderful spot called Christie's Seafoods.

A few days later we're driving west to the Blue Mountains outside the city, and I realize we're within striking distance of the Asian district of Cabramatta. The neighborhood was originally at the head of a creek where mangrove worms once lived, and the locals were supposedly named Cah-brogal, or "the people who eat worms." No worms in the souklike markets these days, but Hannah is fascinated by the blue swimmer crabs that look like bright enameled brooches, the rather scary Balmain bugs and the whole octopus.

At the recommendation of an excellent Sydney blog called Grab Your Fork, we decide to have lunch at Duc-Thanh, a restaurant at the end of a crowded arcade overlooking a parking lot. We order soda lemon salty, a reviving mix of crushed ice, lemon juice, soda water and salt, and the lemongrass chicken with vermicelli, which sits on a bed of fresh mint leaves. In the dining room, we're surrounded by Vietnamese families eating lunch—stroller parked at one end of the table, granny at the other—and friends enjoying a pot of tea. The food is fabulous, the atmosphere relaxed and friendly. I'd happily eat here weekly.

We do ultimately find Hannah's Pies, across from the Powerhouse Museum in Ultimo. This small savory-pie factory makes and supplies the famous cart Harry's Cafe de Wheels, which is located in nearby Haymarket and has another cart farther east in Woolloomooloo. We eat a Curry Tiger, a spicy meat pie topped with mashed potato and a ring of mushy peas filled with gravy—simple and delicious.

At the end of our trip, we walk back to the cottage along the moonlit beach as the tide comes in. The seagulls, lorikeets and cockatoos are quiet, misty rain covers our shopping bags and the view of central Sydney is changing yet again: It now resembles a pile of giant Christmas tree lights shrouded in silver fog.

Back in our cottage, Jeff gets ready to prepare a bruschetta with the sweet potato and cottage cheese we bought during the day's expedition. There's a family to feed and suitcases to pack, as tomorrow we head a thousand miles north to the humid tropics of Queensland and another kitchen.

Jake Tilson, author of A Tale of 12 Kitchens, is also an artist and designer whose work has been exhibited worldwide.