Peru’s lomo saltado is fusion cooking at its easiest and most approachable, a quick stir-fry of soy-marinated beef, tomatoes and hot peppers that reflects the country’s cultural — and culinary —influences, from Incan farmers to Chinese immigrants. Ancient settlers in the Andes Mountains cultivated peppers and potatoes. Spanish colonizers introduced beef and sheep. Centuries later, an influx of indentured Chinese workers came, bringing ingredients such as soy sauce and ginger, as well as stir-frying.