Overall, the food of Guangdong (also known as Canton in Cantonese) focuses more on fresh flavours, light dishes and that all important umami taste rather than the fiery chillies and numbing peppercorns of northern regions like Sichuan and Hunan. But there are certain oils used for dipping, flavouring soups and as a base for sauces that are the exception to this rule. There’s shacha sauce, which combines chillies, brill and dried shrimp for a deep, very savoury, slightly spicy flavour, and Chiu Chow chilli oil (also known as Chaozhou sauce), which has taken the world by storm.

Chiu Chow chilli oil is quite simple in its preparation, but the resulting flavour is punchy and complex – a perfect combination of chilli and garlic which doesn't overpower and gradually builds in heat. Chillies preserved in salt, a huge amount of chopped garlic and soy sauce are added to a mix of soybean and sesame oil and left to infuse. While many other chilli oils are strained before bottling, producers leave the little bits of chilli and garlic in the jar on purpose, as this is where the most intense flavour and aroma comes from. This effectively gives cooks two ways of using the oil – either as a pure, spicy liquid, or something with a bit more texture and umami-laden chewiness.

In Guangdong the oil is typically served at the table for diners to add to whatever they please, but it’s also used to dress aromatic beef stews, to flavour broths containing all sorts of meats and vegetables and as a dipping sauce for steamed dumplings. It’s popular outside of Guangdong, and in places such as Hong Kong the oil itself is used for stir-frying, while the dregs at the bottom are kept for finishing dishes that benefit from a little kick of spice. Outside of Chinese cuisine, it can be used as a marinade for steaks, spread on a cheese sandwich, stirred through hummus or even as a flavour for ice cream. There are an awful lot of chilli oils in the world, but Chiu Chow is the only one to include an aromatic, chewy, flavourful sediment, which ensures it won’t sit languishing in a cupboard for months on end.