One-Pot Tomato Basil Lentil Soup – Cozy, Simple, and Full of Flavor

Tomato basil and lentils make a cozy team: bright, herbaceous, and satisfying without being heavy. This one-pot soup comes together with pantry staples and fresh basil, and it tastes like it simmered all day. It’s budget-friendly, naturally vegan, and great for weeknights or meal prep.

Everything cooks in one pot, so cleanup is easy. If you’re craving a bowl that’s hearty, comforting, and clean, this is it.

What Makes This Recipe So Good

• One pot, minimal mess: The entire soup cooks in the same pot, from sautéing the aromatics to simmering the lentils.
• Deep flavor fast: Tomato paste, garlic, and a quick basil bloom create layered flavor in under an hour.
• Hearty and satisfying: Red or brown lentils add protein and fiber, making this a full meal with bread or a salad.
• Flexible ingredients: Use canned tomatoes, broth or water, and whatever veggies you have on hand.
• Meal-prep friendly: Keeps well and tastes even better the next day as the flavors meld.

Shopping List

• Olive oil
• Yellow onion
• Carrots
• Celery (optional but recommended)
• Garlic
• Tomato paste
• Crushed or diced canned tomatoes (28-ounce can)
• Vegetable broth or water
• Dry lentils (red or brown/green)
• Fresh basil
• Dried oregano or Italian seasoning
• Bay leaf (optional)
• Red pepper flakes (optional)
• Sugar or balsamic vinegar (a pinch/splash to balance acidity)
• Salt and black pepper
• Lemon (for finishing)
• Parmesan rind or grated Parmesan (optional if not vegan)
• Coconut milk or cream (optional for creamier texture)

Step-by-Step Instructions

1. Rinse and sort the lentils. Place 1 cup of dry lentils in a fine-mesh strainer, rinse under cold water, and remove any small stones. Red lentils cook faster and give a creamier texture. Brown/green lentils hold their shape and offer more bite.
2. Prep your aromatics. Dice 1 medium onion, 2 carrots, and 1–2 celery stalks. Mince 3–4 garlic cloves.

   Roughly chop a generous handful of basil (about 1 cup loose leaves), keeping some for garnish.

3. Warm the pot. In a large pot or Dutch oven, heat 2 tablespoons olive oil over medium heat. Add onion, carrot, and celery. Season with a pinch of salt.

   Cook 5–7 minutes, stirring, until softened and lightly golden.

4. Add garlic and tomato paste. Stir in the garlic and 2 tablespoons tomato paste. Cook 1–2 minutes until the paste darkens slightly and smells sweet. This step builds a richer tomato base.
5. Layer the liquids and seasonings. Pour in a 28-ounce can of crushed or diced tomatoes and 4 cups of vegetable broth (or water).

   Add 1 teaspoon dried oregano or Italian seasoning, a bay leaf if you have one, and a pinch of red pepper flakes for gentle heat.

6. Add lentils and simmer. Stir in the rinsed lentils. Bring to a gentle boil, then reduce to a simmer. Cover partially and cook, stirring occasionally:
   • Red lentils: 20–25 minutes
   • Brown/green lentils: 30–35 minutes

   If the soup gets too thick, add more broth or water 1/2 cup at a time.

7. Tune the acidity. Taste.

   If the tomatoes are sharp, add 1/2 teaspoon sugar or a splash of balsamic vinegar to balance. Keep salt modest until the end if you’re using a Parmesan rind.

8. Stir in basil and finish. When lentils are tender, remove the bay leaf. Stir in most of the chopped basil and a squeeze of lemon.

   For creaminess, add 1/4 cup coconut milk or a splash of cream. For savory depth, simmer the soup for 5 more minutes with a Parmesan rind if not vegan, then remove it.

9. Adjust seasoning. Taste and add salt and black pepper as needed. If you want a smoother texture, blend a few cups of soup and return it to the pot, or use an immersion blender for a few quick pulses.
10. Serve. Ladle into bowls and top with fresh basil, a drizzle of olive oil, and grated Parmesan (or nutritional yeast) if you like.

    Crusty bread on the side is never a bad idea.

Storage Instructions

• Fridge: Cool completely, then refrigerate in a sealed container for up to 5 days.
• Freezer: Freeze in portions for up to 3 months. Leave a little headspace for expansion. Thaw overnight in the fridge.
• Reheat: Warm gently on the stove over medium-low heat with a splash of water or broth.

  Stir occasionally to prevent sticking.

• Texture note: Red lentils thicken as they sit. Just loosen with liquid and re-season to taste.

Why This is Good for You

• Protein-packed: Lentils deliver plant-based protein that keeps you full and supports muscle repair.
• Fiber-rich: The combo of lentils, tomatoes, and veggies supports digestion and steady energy.
• Antioxidants and vitamins: Tomatoes bring lycopene; basil adds vitamin K and aromatic compounds that make healthy food taste great.
• Balanced meal: Carbs from lentils and veggies, protein from legumes, and healthy fats from olive oil create a satisfying bowl.

Pitfalls to Watch Out For

• Undercooked lentils: Taste before serving. If they’re chalky in the center, keep simmering and add a splash of liquid.
• Harsh acidity: Canned tomatoes vary.

  Balance with a pinch of sugar or balsamic and a squeeze of lemon at the end.

• Over-salting: If using a Parmesan rind or salty broth, salt lightly and adjust at the end.
• Mushy vegetables: Dice veggies evenly and sauté until just golden before adding liquids. This helps them hold texture.
• Too thick or thin: Control consistency with extra broth or by simmering uncovered a few minutes to reduce.

Recipe Variations

• Creamy Tuscan-style: Stir in 1/2 cup coconut milk or cream and add a handful of chopped sun-dried tomatoes.
• Smoky paprika: Add 1 teaspoon smoked paprika with the tomato paste for a deeper, campfire-like flavor.
• Protein boost: Add a can of rinsed white beans in the last 10 minutes of cooking.
• Veggie-packed: Stir in chopped spinach or kale during the last 3–5 minutes. Zucchini or bell peppers can be sautéed with the onion.
• Spicy kick: Increase red pepper flakes or add a swirl of Calabrian chili paste.
• Herby swap: No basil?

  Use parsley and a little fresh thyme, or a spoonful of pesto at the end.

• Gluten-free croutons: Top with toasted chickpeas for crunch instead of bread.

FAQ

Can I use green or brown lentils instead of red?

Yes. Brown and green lentils hold their shape and need roughly 30–35 minutes to become tender. Red lentils cook faster and create a creamier, slightly thicker soup.

Both work well; choose based on your preferred texture.

Do I have to soak the lentils?

No soaking is necessary for red, brown, or green lentils. Just rinse and pick through for debris. Soaking can slightly reduce cooking time, but it’s not required here.

How can I make it creamier without dairy?

Use 1/4–1/2 cup full-fat coconut milk and a brief blend with an immersion blender.

The result is lush without tasting like coconut, especially with basil and tomato.

What if I don’t have fresh basil?

Use 1–2 teaspoons dried basil added with the other dried herbs, and finish with a splash of good olive oil and lemon. If you have pesto, stirring in a spoonful off the heat can mimic the fresh basil vibe.

Can I make this in an Instant Pot?

Yes. Sauté aromatics with tomato paste on Sauté mode, add remaining ingredients (use 3 cups broth for red lentils or 4 for brown/green), then cook on High Pressure: 8 minutes for red lentils, 12 minutes for brown/green.

Quick-release, stir in basil and lemon, and adjust seasoning.

How do I keep leftovers from getting too thick?

Add water or broth when reheating, 1/4 cup at a time, until you reach your preferred consistency. Taste and adjust salt and acid after thinning.

Is this soup freezer-friendly?

Absolutely. It freezes well for up to 3 months.

Red lentils may soften further, but the flavor holds up beautifully.

In Conclusion

This One-Pot Tomato Basil Lentil Soup is simple, affordable, and full of bright, comforting flavor. It leans on pantry staples, welcomes substitutions, and fits weeknights as easily as meal prep. Keep it brothy or make it creamy, add greens or keep it classic—the base is solid either way.

Ladle it into a bowl, finish with fresh basil and a little olive oil, and enjoy a cozy, nourishing meal with minimal effort.