From America's Test Kitchen Season 5: A Soup Supper
A hot bowl of lentil soup provides warm comfort on a cold day and, when properly prepared, tastes great—maybe even better—the next day. We wanted a hearty lentil soup worthy of a second bowl, not the tasteless variety we have so often encountered. While lentilles du Puy are our top choice for lentil soup, almost any lentil (other than red lentils) can be used. To keep the lentils from losing their shape as they cooked, we sweated them with sautéed aromatic vegetables before adding chicken broth to the soup pot. These lentils stayed intact in our final soup, but their flavor was weak. Revisiting this step, we added canned tomatoes and crisp bacon, which gave our lentils a huge flavor boost. And because we cooked the bacon first, we could then use the rendered fat to sauté our vegetables and aromatics, which brought a nice smoky flavor to the soup. Looking for a not too smooth, or too thick, texture we pureed a few cups of the soup and added it back to the pot to warm through. Lentil soup needs plenty of acidity, so we used white wine as part of the broth and finished the soup with balsamic vinegar.
makes about 2 quarts, serving 4 to 6
Lentils du Puy, sometimes called French green lentils, are our first choice for this recipe, but brown, black, or regular green lentils are fine, too. Note that cooking times will vary depending on the type of lentils used. Lentils lose flavor with age, and because most packaged lentils do not have expiration dates, try to buy them from a store that specializes in natural foods and grains. Before use, rinse and then carefully sort through the lentils to remove small stones and pebbles. The soup can be made in advance. After adding the vinegar in step 2, cool the soup to room temperature and refrigerate it in an airtight container for up to 2 days. To serve, heat it over medium-low until hot, then stir in the parsley.