This comforting lentil soup is a perfect weeknight meal that combines the rich flavors of fire-roasted tomatoes and aromatic thyme, all cooked to perfection in an Instant Pot. Perfect for chilly evenings or as a hearty side dish at any gathering, this recipe yields a bowl full of nutritious goodness, packed with fiber and protein. The gentle pressure cooking method ensures that each ingredient retains its best qualities, making it both delicious and easy to prepare.
Ingredients You Will Need
- 2 tablespoons extra-virgin olive oil
- 1 medium yellow onion (chopped)
- 2 celery stalks (chopped)
- 2 cups chopped carrots (about 4 medium)
- 6 kale leaves (stems finely diced, leaves chopped)
- 4 garlic cloves (grated)
- 1 (14-ounce) can diced fire-roasted tomatoes
- ¾ cup uncooked green lentils
- 2 tablespoons white wine vinegar
- 12 fresh thyme sprigs (bundled)
- 1½ teaspoons sea salt
- Heaping ½ teaspoon ground cumin
- Freshly ground black pepper
- 6 cups vegetable broth
- Red pepper flakes
- ½ cup chopped fresh parsley (for garnish)
- Grated Parmesan (for serving, optional)
- Crusty bread (for serving)
Ingredient Notes & Smart Tips
Extra-virgin olive oil: Choose a high-quality extra-virgin olive oil for the best flavor. Look for one with a fruity aroma and a mild taste, as this will complement the other ingredients in the soup.
Onion, celery, and carrots: Ensure that your vegetables are fresh and of good quality. Finely chop the onion and celery to ensure even cooking, while larger chunks work well for the carrots. These vegetables will form the base of the soup, providing a sweet and savory flavor.
Kale: Use fresh kale leaves with bright green color and no signs of wilting. Remove the tough stems and chop the leaves finely to ensure they cook evenly in the soup.
Garlic: Grate the garlic cloves using a microplane or a fine grater for maximum flavor release. This will infuse the vegetables with a rich, aromatic taste that complements the other ingredients.
Thyme and cumin: Use fresh thyme sprigs if available; otherwise, dried thyme can be used as a substitute. For the cumin, opt for ground cumin over whole seeds to ensure it blends well with the other flavors in the soup.
Vegetable broth: Choose a good-quality vegetable broth that is low in sodium and free from artificial additives. This will enhance the overall flavor of the soup without overpowering it.
Step-by-Step Cooking Instructions
- Sauté the Vegetables: Begin by selecting the Sauté function on your Instant Pot, setting the level to medium heat and timing for 8 minutes. Once the pot is preheated, carefully drizzle in the olive oil. Add the chopped onion, celery, and carrots to the pot. Cook these vegetables until they soften and become lightly golden, stirring occasionally to prevent burning. This step is crucial as it sets the foundation of flavors for your soup. You should notice a sweet aroma emanating from the vegetables as they cook.
- Add Remaining Ingredients: Once the vegetables are soft, add the kale stems, grated garlic, diced fire-roasted tomatoes, uncooked green lentils, white wine vinegar, thyme bundle, sea salt, ground cumin, and a few grinds of freshly ground black pepper. Stir well to combine all ingredients thoroughly. The combination of these flavors will create a complex and delicious base for your soup. Ensure that the vegetables are evenly coated with the spices and herbs.
- Pressure Cook: Pour in 6 cups of vegetable broth, making sure not to overflow the pot. Secure the lid on the Instant Pot, ensuring that the valve is set to the sealing position. Pressure cook on high for exactly 15 minutes. This step ensures that all ingredients are cooked through and tender without losing their nutritional value or texture. The pressure cooking process will also enhance the flavors of the soup, creating a rich and satisfying broth.
- Release Pressure: Once the 15-minute cook time is up, allow the Instant Pot to release pressure naturally for 20 to 30 minutes. This slow release process will help retain the flavors and textures of your soup. During this time, you can prepare garnishes or other accompaniments. When the float valve drops, carefully remove the lid and stir in the chopped kale leaves. Add a pinch of red pepper flakes for some heat, and season to taste with additional salt and pepper if needed.
- Serve: Remove the thyme bundle from the soup and discard it. Garnish each serving bowl with chopped fresh parsley and grated Parmesan cheese, if desired. Serve hot with a slice of crusty bread on the side to soak up every last drop of delicious broth. The combination of the creamy lentils and the vibrant flavors of the vegetables will make this soup a comforting meal that is sure to satisfy any craving.
Extra Cooking Tips for Better Results
- Always preheat your Instant Pot before adding ingredients to ensure even cooking.
- Stir the soup occasionally during pressure cooking to prevent sticking or burning at the bottom of the pot.
- Taste and adjust seasoning as needed after releasing the pressure, as flavors may intensify.
Serving Suggestions
This lentil soup pairs wonderfully with a simple green salad or a side of roasted vegetables. For an extra boost of flavor, consider adding a dollop of Greek yogurt or sour cream to each bowl before serving.
Storage and Make-Ahead Tips
Store any leftover soup in an airtight container in the refrigerator for up to 3 days. Reheat gently on the stove over low heat, stirring occasionally, until heated through. For longer storage, freeze portions in freezer-safe containers for up to 2 months.
Recipe Variations & Substitutions
Add a Protein: For an extra protein boost, add cooked chicken or turkey pieces during the last 5 minutes of cooking. This will infuse the soup with additional flavor and texture.
Use Dried Lentils: If you prefer using dried lentils, soak them overnight before adding to the pot. Adjust the cooking time accordingly, as they may require longer to cook through.
Experiment with Herbs: Feel free to experiment with different herbs like rosemary or oregano for a unique twist on this classic soup recipe.
Frequently Asked Questions (FAQ)
Q: Can I use canned lentils instead of dried?
A: Yes, you can use canned lentils. Drain and rinse them before adding to the pot. Adjust the cooking time slightly as they may cook faster than dried lentils.
Q: How do I know when the soup is done?
A: The soup will be ready once it has reached the desired consistency, which should be thick and creamy with tender vegetables and cooked lentils. Taste to ensure it’s seasoned correctly before serving.
Q: Can I make this recipe in a regular pot on the stove?
A: While you can certainly cook this soup on the stovetop, using an Instant Pot will save time and effort by pressure cooking the ingredients. If you choose to use a regular pot, increase the cooking time significantly as it won’t be pressurized.
Q: How do I store leftovers?
A: Store leftover soup in an airtight container in the refrigerator for up to 3 days or freeze portions for up to 2 months. Reheat gently on the stove over low heat, stirring occasionally, until heated through.