I'm very comfortable being in my thirties and single but if I lived in Vietnam I'm not sure I'd feel the same. That's because I'd probably be written off as a spinster and left to gather dust on some lonely shelf. I'm told the reason that so many Vietnamese women fall victim to such a fate is because they have bad broth. Yes, bad broth. Not halitosis, but a questionable ability to make clear soup that apparently is essential for a successful Vietnamese marriage.

During courtship the prospective mother-in-law assesses the culinary skills of her son's significant other and a bad broth can mean the end of a relationship. This is no joke; I heard it from many sources. Our tour guide Hanh told us of his own experience with 'bad broth girls'. But it was most emphatically expressed by Ms Vy at a cooking class in Hoi An: "The broth must be perfectly balanced for the mother-in-law or there will be no wedding." I was under pressure and struggled to get the perfect balance of the four flavours essential to Vietnamese cooking: hot, sour, salty and sweet. No amount of my mother's novenas was going get me out of this one.

As you can gather, Vietnamese broth is serious business. It's the basis for making ph? (pronounced 'fuh', like 'duh' with an 'f') which is the nation's favourite dish. Ph? is eaten for breakfast, lunch and dinner and Vietnam's streets are full of sidewalk cafes serving up steaming bowls of its beauty. It's a beef noodle soup that dates back to French colonisation. It's believed that 'ph?' is derived from 'pot au feu' - French beef soup. But with the addition of a selection of herbs and spices it becomes an authentic Vietnamese dish.

France isn't the only country to have left its mark on the kitchens of Vietnam. Other countries that have influenced the nation's palate are China, India and Japan. And I got to taste it all on a 12-day food safari, taking me bite by bite from the northern city of Hanoi to Ho Chi Minh City in the south. I got to eat my way through restaurants, family kitchens, markets, coffee houses and, best of all, street stalls. After all, eating is the nation's great passion and it takes centre stage on its streets.

The street food scene in Hanoi's Old Quarter can have one easily addled. The scores of vendors crowd the city's pavements with their smoking charcoal burners and tiny tables and chairs creating a makeshift restaurant. Most stalls offer just one dish, so if you're confused about what to order and not squeamish about what you get, just sit down and a plate will be delivered to you.

Buc Cha is a dish favoured by locals. It's a combination of grilled pork patties, rice noodles, fresh herbs and broth, of course. Another Hanoi speciality is Banh Cuon - steamed rice crepes filled with minced pork, mushroom and prawn. Our guide Hanh told us the best way to enjoy Buc Cha is to add a 'special' ingredient to the dipping sauce. He then squeezed the 'juice' from a large, ugly water beetle into the sauce before chopping up its body for us to try a slice. Its appearance and its taste were incompatible and eating it was one of the biggest culinary surprises of my life. It had a strong but delicious taste of sweet apples; the Vietnamese version on our 'apple drops', but without the sugar high.

Familiarising oneself with Vietnamese food is one of the best ways to become immersed in the culture. All the towns and cities that we visited boasted excellent food markets which provided many photo opportunities. Unfamiliar spices, herbs, fruit and vegetables fill the stalls. The meat section was always interesting. The locals leave nothing of the animal to waste and brains, intestines and heart are all on display. The meats look very fresh; plump, shiny and bright red in colour. A local told me that the average time from slaughter to plate is just three hours. Nearly the same time it takes for me to get from my house to the supermarket and back.

But my Vietnamese food adventure also included other non-food activities. The ice was broken with my tour group on our opening night when we indulged in the first of many Karaoke contests. The itinerary also included sailing on the emerald-green waters of the stunning Halong Bay with its collection of over 2,000 karst limestone islands. You also get the opportunity to be your our own fashion designer in the plethora of tailor shops in Hoi An. They will make anything for a fraction of the price at home.

Leaving the tailors aside, it was Hoi An's food scene that was the town's biggest focus for our tour. Ms Vy doesn't just give advice on how to find a husband; she owns three restaurants in the town and The Morning Glory Cookery School. Our cooking course started off with a bicycle tour around the rice paddies and herb gardens of the area, giving us a greater understanding of the ingredients we later cooked in class.

Another Hoi An gourmet institution is a family-run restaurant, the Bale Well. It's famous for the one dish it serves: barbecued pork and mountains of fresh herbs that are rolled at the table into pancakes and served with a satay sauce. It was a tasty combination, but what was remarkable about eating here is the waitresses' force-feeding methods. They stood at the table and kept rolling pancake after pancake before shoving them into our mouths. Mrs Doyle doesn't have a patch on these women and in this frenzied feast I found a deeper compassion for geese whose livers are destined to become foie gras.

In contrast to this, a few nights later we stayed in a cosy family home in the Mekong Delta, an area famous for its fertile land amongst innumerable rivers and canals. Before our arrival we visited the floating markets and bought the ingredients for dinner which we prepared alongside the ladies of the house. The banquet of spring rolls, elephant ear fish, lemongrass chicken and mango-flavoured sticky rice was devoured while the kids played Gangnam Style on repeat.

Ms Vy, a celebrated television chef, gave us our final cooking class and had the last word. A gentle lady of 61, she emphasised the key to making a good dish is having patience and putting all your love into your cooking. We made another broth and she complimented mine. It turns out I am marriage material after all.

Deirdre Mullins travelled as a guest of Intrepid Travel. The Real Food Adventure Trip – Vietnam starts in Hanoi and travels to Hoh Chi Minh City over 12 days. Prices start from €1,395 which includes accommodation, some meals, transport in Vietnam, activities, and a service of a local tour leader. Book at: www.intrepidtravel.com/food or call: (01) 524 0071.

To get a taste of Deirdre's Vietnam experience, watch this video made by Intrepid partners The Perennial Plate here.

RTÉ is not responsible for the content of external websites.