Caldo Verde (Portuguese Sausage Kale Soup)
12 ounces linguica sausage, sliced
1 tablespoon olive oil
1 onion, finely diced
1 pinch salt
3 pounds russet potatoes, peeled and sliced 1/8 to 1/4 inch thick
2 teaspoons salt, plus more as needed
2 quarts chicken broth or water
2 pounds kale - trimmed, chopped, rinsed, drained
1 pinch cayenne pepper (optional)
1Slice sausage into 1/4-inch rounds. Heat oil in a pot over medium-high heat. Add sausage and saute until sausage begins to turn brown and renders some fat, 3 to 5 minutes. Transfer with a slotted spoon to a dish. Reduce heat to medium-low; add onions and pinch of salt salt. Stir and cook until softened, 4 to 5 minutes.
2Transfer potatoes to pot. Sprinkle in 2 teaspoons salt. Pour in chicken broth. Increase heat to high and bring to a simmer. Reduce heat to medium-low; simmer until potatoes are tender, 8 to 10 minutes.
3When potatoes are tender, carefully mash them in the broth with a potato masher until broken up or completely mashed. Add kale, a handful at a time. Transfer browned sausage to soup. Bring to a simmer over medium-high heat. Reduce heat to medium-low and simmer until greens are tender, about 45 minutes.