
SERVES 4 TO 6
Trim tough stems from 1 lb. spinach and rinse.
Cook 1 lb. cleaned, sliced leeks in butter with salt, stirring, until softened, about 5 minutes.
Add 4 cups vegetable or chicken broth and 1 large chopped, peeled Yukon Gold potato. Bring to a boil, covered; then simmer until potatoes are tender, 10 to 15 minutes. Add spinach and cook until wilted, about 1 minute.
Puree soup in a blender in batches. Reheat in pan, thinning with more broth if you like. Season with salt and freshly ground black pepper.
Top with croutons