coconut milk replaces cow's milk in making a custard. These dishes were said to have been brought to Thailand in the 17th century by Maria Guyomar de Pinha, a woman of mixed Japanese-Portuguese-Bengali ancestry who was born in Ayutthaya, and became the wife of Constantine Phaulkon, a Greek adviser to King Narai. The most notable influence from the West must be the introduction of the chili pepper from the Americas in the 16th or 17th century. It, and rice, are now two of the most important ingredients in Thai cuisine. During the Columbian Exchange, Portuguese and Spanish ships brought new foodstuffs from the Americas including tomatoes, corn, papaya, pea eggplants, pineapple, pumpkins, culantro, cashews, and peanuts. Regional variations Regional variations tend to correlate to neighboring states (often sharing the same cultural background and ethnicity on both sides of the border) as well as climate and geography. Northern Thai cuisine shares dishes with Shan State in Burma, northern Laos, and also with Yunnan Province in China, whereas the cuisine of Isan (northeastern Thailand) is similar to that of Southern Laos,and by Vietnamese cuisine to its east. Southern Thailand, with many dishes that contain liberal amounts of coconut milk and fresh turmeric, has that in common with Indian, Malaysian, and Indonesian cuisine. Thai cuisine is more accurately described as five regional cuisines, corresponding to the five main regions of Thailand: Bangkok: cuisine of the Bangkok metropolitan area, with Teochew and Portuguese influences. In addition, as a capital city, Bangkok cuisine is sometimes influenced by more dedicated royal cuisine. Tastes and looks of food in Bangkok have changed somewhat over time as they have been influenced by other cuisines such as Asian, European or Western countries. Central Thai: cuisine of the flat and wet central rice-growing plains, site of the former Thai kingdoms of Sukhothai and Ayutthaya, and the Dvaravati culture of the Mon people from before the arrival of Siamese in the area. Coconut milk is one of major ingredients used in Central Thai cuisine. Isan or northeastern Thai: cuisine of the more arid Khorat Plateau, influenced by the culture of Laos and also by Khmer cuisine. Northern Thai: cuisine of the cooler valleys and forested mountains of the Thai highlands, once ruled by the former Lanna Kingdom and home of Lannaese, the majority of northern Thailand. This cuisine shares many ingredients with Isan. Southern Thai: cuisine of the Kra Isthmus which