3 large leeks
2 Tbs. olive oil or butter
4 c. low-sodium chicken broth or mild-tasting vegetable broth
2 lbs. Yukon gold or Russet potatoes, peeled and diced
1 bay leaf
1-2 sprigs fresh thyme (or ½ tsp. dried thyme)
¼ c. chopped fresh parsley (or another chopped fresh herb)
dash of hot sauce (optional)
salt and freshly ground pepper, to taste
Clean the leeks by making a lengthwise cut in them and rinsing them thoroughly under running water. Trim the root ends and the dark green tops; discard. (Alternatively, you can save the tops to make vegetable stock.*) Slice the leeks crosswise into slices about ¼ inch thick.
Heat olive oil or butter in a large (3 or 4 quarts) stockpot over medium heat. When heated, add the leeks and stir to coat. Cover, reduce heat to low, and cook until leeks are softened, about 10 minutes. Stir occasionally if needed to prevent the leeks from browning.
When leeks are softened, add broth, diced potatoes, bay leaf, and thyme. Increase heat to high, bring to a simmer, then reduce heat to a level that maintains a low simmer. Cook until potatoes are tender, about 20 minutes. Remove bay leaf and thyme sprigs and discard. For a chunky soup, use an immersion blender to blend half the soup, or blend half of it in a regular blender, being extremely careful to avoid splashing. For a smoother soup, blend the entire soup with the immersion blender, or blend in a regular blender in two batches (again, be careful to avoid splashes!). Add a few dashes of hot sauce, if using, to taste. Add salt and freshly ground pepper to taste.
Recipe adapted from http://www.simplyrecipes.com/recipes/potato_leek_soup/
* See this link for a method to make your own vegetable stock: http://www.thekitchn.com/how-to-make-vegetable-stock-cooking-lessons-from-the-kitchn-136725