Caldo Verde (Portuguese Potato and Kale Soup With Sausage) Recipe

Name: Caldo Verde (Portuguese Potato and Kale Soup With Sausage) Recipe
Cook time: 45 min
Total time: 45 min
Yield: 6
Ingredients: 2 tablespoons (30g) unsalted butter; 1 medium yellow onion or large leek, finely diced (about 8 ounces; 225g); 3 medium cloves garlic, sliced (about 1 tablespoon; 15g); Kosher salt and freshly ground black pepper; About 6 tablespoons (90ml) extra-virgin olive oil; 1 large russet potato, peeled, quartered, and cut into 1/4-inch slices (about 1/2 pound; 225g); 2 medium Yukon Gold potatoes, peeled, quartered, and cut into 1/4-inch slices (about 1/2 pound; 225g); 6 cups (1.4L) homemade or store-bought low-sodium chicken stock (see note); 1 bunch curly or lacinato kale, tough stems removed, leaves roughly chopped (about 3/4 pound; 340g); 12 ounces (340g) cooked linguiça or other garlicky pork sausage, cut into 1/4- to 1/2-inch slices (see note); Minced fresh chives, for garnish (optional)