At first sight, there aren’t two cuisines more afar than the Thai and South American ones. I have extensively described both and the conclusions are clear. Thais favor complex dishes, heavily spiced balancing several flavors at once. South American cuisines prefer unsophisticated dishes—just burn the meat—with few or no spices. Thais adore blending hot, sour and sweet; most South Americans spice up exclusively with salt, and would claim that saffron is too spicy, and chilies are barbaric. Don’t catch me on the word here; I’m just trying to summarize a lot of data. Bolivians use chilies, but in a limited way, while Thais can also just eat burnt meat if they are ravenous enough.
Then, if ignoring shapes and flavors, something becomes astonishingly obvious. Three main ingredients in the Thai cuisine originate in South America. Peanuts are native from the Chaco wastelands between Bolivia and Paraguay. Papayas come from the Amazonian forests. Other popular ingredients–like guavas, "farang" in Thai, a term used also towards Western travelers–were brought also from South America. Then, the ubiquitous Thai chilies, also originated in the Americas, where they were popular all over until colonial times. Yet, they are used in Thailand in ways that would render them unrecognizable to their original farmers. Most South American would probably refuse to eat an unripe papaya and guava after those being dip in a mixture of hot chili and sugar.
Yet, the undisputable king of South American influence in Thai cuisine is the som tam, a popular salad combining peanuts and papayas.
A fierce Isaan concoction, som tam is often translated as papaya salad. Hearing the popularized English name may be misleading; fruits in Thailand are often eaten unripe adding thus a sour taste to the dish instead of a sweet one. In fact, the Thai name means "sour pounded."
This is the case here, where shredded unripe papayas are mixed with a variety of additional ingredients; the last change enormously, but the most common ones are peanuts and green beans, tomatoes and small fresh water crabs are also popular. Lime and chilies are the main spices added. In Bangkok and adjacent areas, peanuts are generously added. As with most of Isaan dishes, the chilies play an important role, rendering an incredibly hot salad. This is the main dish eaten by street vendors; if looking at their stalls carefully at noon, one will often find a discreetly placed som tam plate. Simply, its heat creates a sense of fullness in the stomach. More often than not, this is a standalone dish, eaten with no additions, though sometimes sticky rice is added. A fork and a spoon are used for eating it; these two are the most popular cutlery used with Thai dishes. The fork is used for putting food on the spoon, which is then used for carrying it into the mouth. A fork is never put in contact with the mouth. Knives—being potential weapons—are never put on the table.
The result is amazing. The core of the dish is made with South American dishes; yet, no one in this continent would recognize som tam or the way it is consumed. Probably they would refuse tasting it, or spit out the first spoon they try. Caramba!