The dressing is used both in salads and as a sauce on sandwiches, especially in fast-food restaurants. It tastes (and appears to be) very similar to fry sauce (called burger sauce in the UK), a 'simpler' version of thousand island dressing commonly used in fast food outlets. Fry sauce is made from similar ingredients: generally tomato ketchup and mayonnaise.
In many areas of Europe, it is known as "American Dressing."
Origins
Thousand Island dressing has been cited in print since at least 1912, but there are multiple conflicting stories about its origins:
Sophia LaLonde invented it at Chicago's Blackstone Hotel in 1910[1] substituting mayonnaise for the yogurt used in Russian dressing, and added pickle relish, chives and sometimes chopped hard-boiled eggs.
Thousand Island dressing is sometimes used as an ingredient in a Reuben sandwich, along with corned beef, sauerkraut, and marble rye bread (although Russian dressing is used in the authentic recipe).
In the 1950s, Thousand Island dressing became a standard condiment, used on sandwiches and salads alike. It is widely used in fast-food restaurants in America. For example:—
Hardee's uses a type of Thousand Island dressing on its Big Twin sandwich.
Subway offers the choice of Thousand Island dressing.
Corner Bakery uses Thousand Island on its "Turkey Derby" sandwich.
Around half of the selections on the menu at Pizza Hut in Hong Kong use a Thousand Island dressing for the base, instead of traditional tomato sauce.[2]
This is the most common salad dressing in Southeast Asia.
"Sandwich spread" sold by Kraft, and other condiment makers, is simply thicker Thousand Island dressing, which can be spread more easily on bread.
Cooks in rural areas, where commercial salad dressings were slower to appear, often made a version of thousand island, with or without pickles, from ingredients which were commonly available. It was typically called simply salad dressing.
Thousand Island dressing is often used as a substitute for fry sauce, a mixture of ketchup and mayonnaise.