- 6 cups water
- 5 medium-sized Maine, Yukon Gold or other starchy potatoes, peeled and quartered (about 5 cups)
- 1 small yellow onion, finely chopped (about 1⁄2 cup)
- 1 tablespoon coarse salt, or to taste
- 1 bunch (1 1⁄2 pounds before trimming) flat-leaf kale or collard greens
- 5 tablespoons olive oil
- 1⁄4 pound chouriço or linguiça sausage, sliced in 1Â¼4-inch rounds
In a 4-quart stockpot, combine water, potatoes and onion. Cover and bring to a boil over high heat. Reduce heat to medium-low, season with salt and simmer until potatoes are very tender, 20 to 30 minutes.
Meanwhile, trim kale leaves, removing thick central stems. Rinse leaves well in sink full of cool water. Lift out to drain. Stack leaves and roll them tightly lengthwise into a log-shaped bundle. Using a sharp knife, cut log into very thin slices, creating a chiffonade of kale. Continue cutting until you have about 6 cups. Set aside.
When potatoes are cooked, use a stick blender or food mill to purée contents of pot to a smooth consistency (or remove potatoes from soup, mash with a fork and return to soup). Return to a boil.
Add greens and olive oil and simmer for about 5 minutes, or until greens are bright green and tender.
In a skillet set over medium-high heat, cook sausage slices, turning to brown on both sides.
To serve, ladle soup into bowls. It is traditional to place one slice of sausage into each bowl and serve the remaining sausage on the side. Serve hot.