This traditional lentil soup recipe is made with green lentils, smoky kielbasa, and hearty veggies for an easy and comforting soup that’s teeming with awesome flavor.
I’m a soup fanatic through and through. I love smooth soups like my butternut squash soup and and creamy soups like my clam chowder, but I also love hearty versions with lots of protein and veg, like my split pea soup with ham and slow cooker Tuscan white bean soup with sausage. This lentil soup falls in the latter camp. It’s packed with healthy vegetables, French green lentils, and kielbasa, for a super filling and cozy meal. The flavor builders in this soup are tomato paste, for depth of flavor, and Dijon mustard and vinegar for zing. Unusual ingredients in a soup but so good in this one. It’s easy to make (you don’t need to fuss with soaking the lentils) and makes great leftovers.
What’s in Lentil Soup
This hearty lentil soup is full of veggies and umami flavor. It’s also packed with protein from lentils and kielbasa, though you could easily make this vegetarian. Here’s what you’ll need to make this lentil soup:
- Olive oil
- Onion
- Kosher salt and freshly ground black pepper
- Celery
- Carrots
- Garlic
- Tomato paste
- Dijon mustard
- French green lentils
- Fresh thyme
- Dried bay leaves
- Chicken stock (use veggie stock to make this vegetarian or vegan)
- Kielbasa sausage–pork or turkey (omit to make this vegetarian)
- Spinach (or try kale, but add it earlier on)
- Red wine vinegar
- Parmesan cheese, for serving
How to Make Lentil Soup
This lentil soup takes some time to cook but it’s really simple to make. Once you get your chop done, it’s smooth sailing. Here’s how to make it:
Soften your onions. (You can certainly cook all your veg at the same time, but I like to give my onions a headstart so they get a little more color and flavor.) Sauté your onions in a Dutch oven or large pot for about 10 minutes on medium heat, stirring occasionally. Reduce to medium-low so the onions don’t get too brown.
Sauté the rest of the veggies. Season with salt and pepper, then sauté the celery, and carrots along with the onions, for five more minutes.
Add your aromatics and the lentils. Stir in the garlic, thyme, tomato paste, and Dijon then cook for one minute. Add the bay leaf, chicken stock, and lentils. Stir, and bring to a boil.
Simmer away. Reduce the heat to a simmer until the lentils are cooked (but not mushy), for about 45 minutes to one hour.
Add the kielbasa, spinach, and red wine vinegar, and cook just to warm the kielbasa and wilt the spinach.
Taste, doctor, and add the finishing touches. If too much liquid has cooked off, add more chicken stock or some water. When adding more liquid, the zing of the Dijon and vinegar may taste diluted. If so, whisk one teaspoon of Dijon mustard into a few spoonfuls of broth in a small bowl, then add back to the broth. Taste the soup to check the doneness of the lentils, and add more salt and pepper as needed. Top with Parmesan before serving.
Is Lentil Soup Really Good for You
This lentil soup is loaded with healthy veggies, including iron-packed spinach. Lentils are also a healthy legume and a great source of protein. Kielbasa delivers extra protein as well. For a lighter lower-fat soup, use turkey kielbasa.
Do I Need to Soak the Lentils
Some recipes will have you soak the lentils first, but there’s really no need. Just make sure you rinse and drain them well, and pick out any debris.
Spices You Could Add to This Lentil Soup
I love the zesty tang Dijon mustard and red wine vinegar bring to this soup, and the subtle aromatics of the fresh thyme. If you want to switch things up, any of the following spice/herb additions would be lovely:
- Ground cumin
- Coriander
- Curry powder
- Fresh rosemary
Lentil Soup
Ingredients
- 3 tablespoons extra-virgin olive oil divided
- 1 large yellow onion finely chopped
- ½ tablespoon kosher salt
- ¼ teaspoon freshly ground black pepper
- 3 stalks celery medium-diced
- 3 carrots medium-diced
- 2 cloves garlic minced
- 2 tablespoons tomato paste
- 1 ½ tablespoons Dijon mustard
- 2 cups dry French green lentils
- 1 tablespoon fresh thyme leaves
- 2 dried bay leaves
- 8 cups chicken stock
- 14 ounces kielbasa sausage halved lengthwise then sliced into coins
- 3 cups packed spinach
- 1 tablespoon red wine vinegar
- freshly grated Parmesan cheese for serving
Instructions
- Add 2 tablespoons of the olive oil to a Dutch oven or large, heavy-bottom pot over medium heat. Add the onions and sauté for 10 minutes, stirring occasionally (reduce to medium-low if onions start browning). Add 1 tablespoon of olive oil, salt and pepper, celery, and carrots. Sauté for 5 more minutes. Stir in the garlic, thyme, tomato paste, and Dijon, and cook for 1 minute. Add the bay leaves, chicken stock, and lentils. Stir and bring to a boil, then reduce the to a simmer. Cook uncovered until the lentils are cooked through, about 45 minutes to 1 hour.
- If too much liquid cooks off, add more chicken stock, or some water. When adding more liquid, the zing of the Dijon and vinegar may taste diluted. If so, whisk one teaspoon of Dijon mustard into a few spoonfuls of broth in a small bowl, then add back to the broth.
- Taste the soup to check the doneness of the lentils, and add more salt or pepper as needed. Remove the bay leaves. Add the kielbasa, spinach, and red wine vinegar, and cook for 2-3 more minutes to warm the kielbasa and wilt the spinach. Top with Parmesan before serving.
