XO sauce is a rich Chinese condiment made from dried scallops and dried shrimp, slowly cooked with chilli, garlic and shallots in oil. It is very savoury, with a gentle heat, and a spoonful goes a long way.
Where to find it
Larger supermarkets sometimes stock a jar in the Chinese section of the world food aisle. A Chinese grocer usually has more choice. Buying online is a good option if no shop near you carries it.
What to check on the jar
Look at the ingredients. Dried scallop and dried shrimp should appear near the top. Cheaper jars use less seafood and more oil and chilli.
A good jar has a layer of chilli oil on top, with the solid pieces settled below. A jar that is mostly oil has less seafood in it.
If a product is marketed mainly as a chilli sauce, it may use the XO name loosely. Read the label to check for dried seafood.
How to use it
Spoon a little over fried rice, noodles, tofu or steamed greens at the end of cooking. It is a finishing condiment, so do not cook it for long. Start with a teaspoon and add more to taste.
Storage
Keep the jar in the fridge once opened, and use a clean spoon each time. Check the label for any date advice from the brand.
For another rich Chinese condiment, see our oyster sauce guide. For a sharp, dark finishing ingredient, read our Chinkiang black vinegar guide, and for a crunchy chilli topping, see our chilli crisp guide.