Sriracha is a chili sauce which originates in Thailand. Outside of Thailand, sriracha has evolved to become slightly different from its original, causing some Thais to be confused when offered sriracha while traveling, and creating equal consternation in visitors to Thailand when they are confronted with Thai-style sriracha. Most Asian markets carry this sauce, and it has become widely popular in many regions of the world, often showing up in very peculiar places as a result.
Whether a bottle of sriracha is made in the original Thai style, or by a company outside of Thailand, it contains chilies which are ground into a paste before being preserved in vinegar, salt, and garlic. The sriracha paste is typically also flavored with garlic, to give it an extra bite. Depending on how much sugar is used, the sauce may be simply incendiary, or hot with a complex layer of sweetness. Many companies also make flavored sriracha with additional ingredients such as lemongrass or lime.
The sauce is named for the Thai port town which originally made it. In Thailand, sriracha is a traditional locally-produced condiment, one among many chili sauces available for purchase. Typically, the sauce is not extremely shelf stable, requiring refrigeration after it is opened as a result; outside of Thailand, sriracha is often made with preservatives so that it can be kept at room temperature, and the texture tends to be thicker.
Sriracha sauce is designed to be used as a condiment, and it has a wide assortment of uses. Many people use it on a variety of Thai dishes to add an extra burst of heat, and it is also used more generally on Asian cuisine. As a result, many Asian restaurants have sriracha available on the table, for those who wish to spice up their food. The sauce has also crossed the boundary of Asian cuisine, appearing with everything from buffalo wings to pizza, and it is sometimes blended with other condiments to make dressings for salads and sandwiches.
The heat of sriracha sauce can vary, depending on the flavor and the manufacturer. As a general rule, the sauce is relatively mild, when compared to other chili sauces, and fans of hot food may drench their food in sriracha to achieve the desired level of heat. The tangy zing of the garlic and the sweet hit from the sugar also add a layer of complexity to sriracha which is appreciated by some consumers.