Tony Tan's guide to making Hakka salt-baked chicken

It's not a dish you come across in many Chinese restaurants, but if you haven't tasted salt-baked chicken (yan ju ji, in Mandarin), you're in for a treat.

It has had a fascinating journey around the world. It all began with a group of Chinese who fled their homes in central China almost 2,000 years ago and, over centuries and after waves of migration, finally settled in the highlands around Meizhou in Guangdong province and Yongding in Fujian province.

Viewed by the local population with suspicion and at times hostility, these nomads were known as the Hakka, meaning guest families. Imbued with a hardy spirit and gritty tenacity, they cultivated lands no one wanted, and a certain frugality defines their cooking. Salt, pickles, preserved greens and soy sauce feature extensively in their home-spun dishes. Over the centuries, the Hakka people have migrated overseas, too, mostly to South East Asia, but as far as Jamaica and Peru.

While they've adapted their food with local ingredients in the countries where they've settled, one dish has remained faithful to the Hakka spirit: salt-baked chicken.

Legend has it that it was invented in the homes of salt merchants. Buried in hot salt to bake, the bird has a clarity of flavour that's pure magic. But, as with many straightforward dishes, success relies on some essential considerations. For starters, the dish has few embellishments so a good organic, truly free-range chicken is essential.

Traditionally coarse rock salt is heated in a hot wok until it takes on the characteristic smoky fragrance, or wok hei, for the chicken to absorb when it's baked (I've skipped this step here and heated the salt in an oven).

To enhance the flavour of the chicken, it's typically marinated with spring onions, good five-spice powder, Shaoxing rice wine and the all-important fresh sand ginger (Kaempferia galanga). The fragrance of this member of the ginger family is like a cross between white pepper and ginger. Called sha jiang in Mandarin and kencur in Indonesian, it's hard to find fresh, but it's sold dried in pieces or ground in good Asian grocers.

I first learnt how to make this dish years ago from my brother-in-law, who was taught by a Hakka neighbour. Along with the usual spices, he also placed dang gui, Chinese angelica root, in the cavity, and wrapped the chicken with lotus leaves to add their fragrance. He then baked the bird in a massive clay pot over a charcoal brazier. He'd shred the cooked chicken and serve it with a few dipping sauces such as the ginger and spring onion sauce here.

Since then, I've kept faithful to the traditional technique, though here I bake the chook in an oven. It may not be as soulful and authentic, as some purists would argue, but I've retained the sand ginger. I also usually heat some of the salt in a wok for the fragrance (if I'm not doing it all in the wok) and bake the rest in a hot oven. Then I wrap the marinated chicken with non-stick kitchen paper and cocoon it in the hot salt to bake.

While the chicken is baking, I make the ginger and spring onion sauce with a mortar and pestle. I also squeeze some lemons for juice, which I offer separately as another dipping sauce.

Once the chook is cooked, rest it and allow the salt to cool a little, then brush it off carefully, unwrap the layers of paper and savour the mouth-watering fragrance of this buried treasure.

Baking in a salt crust is a culinary tradition that spans many cultures. What interests me is how the Hakka people came to learn this cooking method, and why it has stood the test of time. The second part of the question is easier to answer: it works so well. The salt crust insulates the chicken from direct heat, thus yielding the most evenly cooked, juicy bird. 

Interestingly, few Chinese restaurants feature this delectable dish. Those that do tend to take a shortcut and steam or poach a brined chicken, which is not the real thing. Once you've made this recipe, I'm certain you'll return to it again and again.