What is it?
According to one version of the story, in the 1980s a chef at the Peninsula Hotel in Hong Kong decided to make a top-shelf sauce that would blow people's minds, taste buds and budgets. He named this paste-like sauce, made from expensive dried scallops, dried shrimp, chilli and a variety of other ingredients, after the equally pricey Courvoisier XO cognac.
Chefs from around the globe who tried the new sauce in Hong Kong took the concept back to their kitchens and reverse-engineered it. That is why although scallops and shrimp are key, there is no one recipe for XO sauce, and why some call for other umami-rich ingredients such as fish sauce and preserved pork.
Why do we love it?
It reeks of luxury, conspicuous consumption and outrageous deliciousness. It has a wonderfully chewy and slightly crunchy texture, chilli heat and oily unctuousness. XO is also aromatic with its melange of garlic, rice wine and different sauces.
But it's the powerful umami kick that makes XO the emperor of condiments. Dried scallops and shrimp are packed with yum-inducing amino acids called glutamate and inosinate. When you put these two together they make everything you taste afterwards many times more delicious.
Stir-fried pipis with XO sauce at XOPP in Sydney. Photo: Edwina Pickles
Who uses it?
Sydney restaurateur Billy Wong named his Haymarket restaurant XOPP after the dish. He says the sauce "adds layers, complexity and deliciousness to everything it touches, especially meat and seafood". His top-selling dish is pipis stir-fried in XO sauce, based on the recipe from his parents' much-loved but recently closed Golden Century.
One of the first restaurants in Australia to develop their own XO recipe was Flower Drum in Melbourne. "I love lobster in XO sauce with egg noodles," says general manager Jason Lui. "You need to have something like noodles or crunchy vermicelli to soak up the sauce. We use spinach for this in our takeaway XO king prawns." Lui says XO can be difficult to pair with drinks but try a pinot noir or a German wheat beer.
How do you use it?
Sparingly – a little goes a long way. Making your own XO sauce is not difficult but does take a little time. You can buy many of the ingredients at Asian grocers or online from asiangrocerystore.com.au. Being a modern condiment, there are no strict traditions.
It goes with anything savoury, from wok-fried eggs to a dressing for stir-fried asparagus. Stir half a teaspoon through roast chicken gravy for a rich zing, add a spicy hit to congee, make a healthy chicken and vegetable stir-fry or luxuriate in a rich dish of wagyu beef and XO.
Where do you get it?
Food brands Lin Lin and Ayam produce XO sauces that are sometimes stocked by supermarkets. For more variety head to Asian grocers and look out for Lee Kum Kee for about $30 for 220g. Remember, you get what you pay for.
Locally made Golden Century brand XO can be bought directly from XOPP in Haymarket or online from Asian grocer thaikee.com.au and will be available soon from providoor.com.au. Melbourne restaurant Lee Ho Fook sells its house-made version at leehofook.com.au.