Lentil Vegetable Soup with Diced Tomatoes

Name: Lentil Vegetable Soup with Diced Tomatoes
Prep time: 20 min
Cook time: 48 min
Total time: 1 h 8 min
Yield: 6 servings
Cuisine: American
Ingredients: 3 tablespoons (45 ml) extra-virgin olive oil; 1 large (about 10 oz) (285 g) yellow onion, peeled and cut into ½-inch (1 cm) dice; 3 medium (about 10 oz) (285 g) carrots, peeled and cut into ½-inch (1 cm) dice; 3 medium (about 6 oz) (170 g) celery stalks, cut into ½-inch (1 cm) dice; 4 cloves (12 g) garlic cloves, minced; 2 tablespoons (32 g) tomato paste; 1 teaspoon (2 g) ground cumin; 1 teaspoon (1 g) dried thyme; 1½ cups (300 g) dried green or brown lentils, rinsed and drained; 1 can (14.5 oz) (411 g) canned diced tomatoes, with their juices; 6 cups (1420 ml) low-sodium vegetable broth; 2 whole leaves (1 g) dried bay leaves; 2 medium (about 12 oz) (340 g) zucchini, quartered lengthwise and sliced ½ inch (1 cm) thick; 1½ teaspoons (9 g) kosher salt, plus more to taste; ½ teaspoon (1 g) black pepper, freshly ground; 1 tablespoon (15 ml) red wine vinegar; ¼ cup (15 g) fresh flat-leaf parsley, roughly chopped, for serving (optional)

From the MyKitchenBank Kitchen

A hearty, one-pot American-style soup of green lentils, carrots, celery, zucchini and canned diced tomatoes, simmered with garlic, thyme and a splash of red wine vinegar for brightness. Vegan, filling and easy to make ahead.

Prep: 20 min
Cook: 48 min
Wait: 5 min
Total: 1 hr 13 min
Makes: About 9 cups (2.1 L), 6 generous servings

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Ingredients

6 servings

3 tablespoons (45 ml) extra-virgin olive oil
1 large (about 10 oz) (285 g) yellow onion, peeled and cut into ½-inch (1 cm) dice
3 medium (about 10 oz) (285 g) carrots, peeled and cut into ½-inch (1 cm) dice
3 medium (about 6 oz) (170 g) celery stalks, cut into ½-inch (1 cm) dice
4 cloves (12 g) garlic cloves, minced
2 tablespoons (32 g) tomato paste
1 teaspoon (2 g) ground cumin
1 teaspoon (1 g) dried thyme
1½ cups (300 g) dried green or brown lentils, rinsed and drained
1 can (14.5 oz) (411 g) canned diced tomatoes, with their juices
6 cups (1420 ml) low-sodium vegetable broth
2 whole leaves (1 g) dried bay leaves
2 medium (about 12 oz) (340 g) zucchini, quartered lengthwise and sliced ½ inch (1 cm) thick
1½ teaspoons (9 g) kosher salt, plus more to taste
½ teaspoon (1 g) black pepper, freshly ground
1 tablespoon (15 ml) red wine vinegar
¼ cup (15 g) fresh flat-leaf parsley, roughly chopped, for serving (optional)

Equipment (5)

5- to 6-quart (4.7–5.7 L) heavy-bottomed soup pot or Dutch-style pot with lid
Wooden spoon
Fine-mesh sieve
Chef's knife and cutting board
Ladle

Steps

Before you start

Use green or brown lentils; red lentils break down completely and will change the texture.
Rinse the lentils in a fine-mesh sieve and pick out any small stones or shriveled lentils.
Chop all vegetables before you start heating the pot; the first steps move quickly.
Hold back the salt until the lentils are tender, since salt and acid added too early can slow softening.

1
Soften the aromatics
- Set a 5- to 6-quart heavy-bottomed soup pot over medium heat and add the olive oil.
- When it shimmers, add the onion, carrots and celery.
- Cook, stirring often, for 8 minutes.
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Ready when: Onion is translucent and the edges of the vegetables are just starting to soften; no browning needed.
Tip: If the vegetables start to brown, lower the heat slightly.
2
Bloom garlic and spices
- Stir in the garlic, tomato paste, cumin and thyme.
- Cook, stirring constantly, for 1½ to 2 minutes.
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Ready when: Tomato paste darkens to brick red and the pot smells fragrant.
Tip: Scrape the bottom as you stir so the paste doesn't scorch.
3
Add lentils and liquid
- Add the rinsed lentils, diced tomatoes with their juices, vegetable broth and bay leaves.
- Stir well, scraping up any browned bits from the bottom of the pot.
- Raise the heat to high and bring to a boil.
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Ready when: Large bubbles break across the whole surface.
4
Simmer the lentils
- Reduce the heat to medium-low so the soup bubbles gently.
- Partially cover the pot with the lid slightly ajar and simmer for 20 minutes, stirring once or twice.
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Ready when: Lentils are partly tender but still have a firm bite in the center.
Tip: Skim off any foam that collects on the surface.
5
Add the zucchini
- Stir in the zucchini, 1½ teaspoons salt and the pepper.
- Return to a gentle simmer, partially covered, and cook 12 to 15 minutes more.
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Ready when: Lentils are fully tender and creamy inside but still hold their shape; zucchini is soft but not mushy. Bite a few lentils to check.
Tip: If the soup looks thick, add ½ cup (120 ml) hot water or broth.
6
Finish and season
- Remove and discard the bay leaves.
- Stir in the red wine vinegar.
- Taste and add more salt, up to ½ teaspoon at a time, until the flavors taste bright and full.
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Ready when: Soup tastes savory with a lift of acidity, not flat.
Tip: Season after the lentils are tender for the best flavor and texture.
7
Rest and serve
- Take the pot off the heat and let it rest, uncovered, for 5 minutes so it thickens slightly.
- Ladle into bowls and top with chopped parsley, if using.
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Ready when: Soup is thick and spoonable, not watery.

Good to know

Tips

Don't skip the final splash of vinegar; it wakes up the whole pot.
Keep the simmer gentle; hard boiling splits lentil skins and makes the soup muddy.
For a creamier body, blend 2 cups of the soup with an immersion blender or in a blender and stir it back in.
Add a handful of baby spinach or chopped kale in the last 3 minutes for extra greens.

Make ahead

The soup tastes even better the next day. Cook completely, cool, and refrigerate up to 4 days; add a splash of water or broth when reheating because it thickens as it sits.

Storage & reheating

Room temperature: up to 2 hours. Refrigerator: up to 4 days in an airtight container. Freezer: up to 3 months in freezer-safe containers, leaving 1 inch (2.5 cm) headspace. Thaw overnight in the fridge and reheat in a pot over medium-low heat, stirring, until steaming hot (165°F/74°C), thinning with water or broth as needed.

Substitutions

dried green or brown lentils → French (Puy) lentils. Hold their shape well; cook time is similar, check at 30 minutes.
zucchini → yellow squash or 2 cups chopped green beans. Green beans may need a few extra minutes.
red wine vinegar → fresh lemon juice. Use 1 tablespoon (15 ml).
low-sodium vegetable broth → chicken broth. Same amount; this makes the soup no longer vegan.