Kale soup is any soup that has kale as one of its main ingredients. The kale plant is hardy and grows in many areas around the world. Depending on the area where the kale is growing and that area's local culinary traditions, the soup can take on different characteristics. The version that is most often considered classic kale soup is from Portugal. Portuguese kale soup contains kale, potatoes and sausage cooked in chicken stock.
The strong flavor and thick, meaty leaves of a kale plant make them perfect for long, slow cooking. By boiling the leaves in a liquid, most of the vitamins and minerals are preserved and the water or stock is flavored. Cooking kale this way also softens the leaves so they are easier to eat and digest.
Traditional Portuguese kale soup begins by sautéing onions, red pepper and garlic. A Portuguese sausage called linguica is added to the oil to saute. A number of other ingredients are added, including potatoes and tomatoes. Water and chicken stock are added along with kidney beans and, finally, the kale. This entire soup is taken to a boil and then allowed to simmer for 20 to 30 minutes.
In Africa, specifically southeastern Africa, kale can be boiled in coconut milk. The resulting soup later has ground peanuts and spices added to it. This is poured over rice to be eaten or can be served over ugali, a type of cornmeal mush.
Brazil has a classic dish called caldo verde, which means green soup in Portuguese. It is nearly identical to Portuguese kale soup except that shaved beef is substituted for the sausage. The robust taste of the dark kale greens is not lost when paired with the shaved beef in this dish.
In Kashmir, kale is harvested slowly over the course of the entire season, causing the plant to produce more leaves than usual. The leaves are used in a simple kale soup made from water, salt and oil. This soup is served over rice or alongside meat.
Variations of kale soup in the United States include a vegetarian soup that either replaces the meat with firm tofu or simply does without meat and its substitute. Kale also is frequently added to vegetable soup to give it body and extra nutrition. Other popular variations are chicken soups that include finely diced kale and bean soups that integrate the distinctive kale flavor into a rich base.
