Considerable evidence suggests that either the United States or Germany (the city of Hamburg) was the first country where two slices of bread and a ground beef patty were combined into a "hamburger sandwich" and sold, it really boils down to who was able to prove it and not hearsay. There is some controversy over the origin of the hamburger because its two basic ingredients, bread and beef, had been prepared and consumed separately for many years in different countries before their combination. Shortly after its creation, the hamburger quickly included all of its currently typically characteristic trimmings, including onions, lettuce, and sliced pickles. After various controversies in the 20th century, including a nutritional controversy in the late 1990s, the burger is now readily identified with the United States, and a particular style of cuisine, namely fast food. Along with fried chicken and apple pie, the hamburger has become a culinary icon in the United States. The hamburger's international popularity demonstrates the larger globalization of food that also includes the rise in global popularity of other national dishes, including the Italian pizza, Chinese fried rice and Japanese sushi. The hamburger has spread from continent to continent perhaps because it matches familiar elements in different culinary cultures. This global culinary culture has been produced, in part, by the concept of selling processed food, first launched in the 1920s by the White Castle restaurant chain and its founder Edgar Waldo "Billy" Ingram and then refined by McDonald's in the 1940s This global expansion provides economic points of comparison like the Big Mac Index, by which one can compare the purchasing power of different countries where the Big Mac hamburger is sold. Beginning Before the disputed invention of the hamburger in the United States, similar foods already existed in the culinary tradition of Europe. The Apicius cookbook, a collection of ancient Roman recipes that may date to the early 4th century, details a preparation of beef called isicia omentata; served as a baked patty in which beef is mixed with pine kernels, black and green peppercorns, and white wine, isicia omentata may be the earliest precursor to the hamburger. It is not known when the first restaurant recipe for steak tartare appeared. While not providing a clear name, the first description of steak tartare was given by Jules Verne in 1875 in his novel Michael Strogoff. There are certain similarities between steak tartare