Full of earthy lentils and a richly seasoned broth, this Instant Pot Lentil Soup is anything but bland. 

While I love using lentils in recipes like Instant Pot Lentil Chili and Lentil Taco Meat, this recipe for Lentil Soup ranks as my favorite. It is an incredibly simple plant-based dinner recipe that is packed with flavor.

Notes on Ingredients & Modifications

• Lentils: You must use dried brown or green lentils, not yellow or red lentils, as they will turn to mush during pressure cooking.
• Broth: Use low-sodium store-bought or homemade vegetable broth, to control the sodium level in this soup. If you are not vegan or vegetarian, replace the vegetable broth with chicken stock.
• Italian Battuto:This Italian combination of celery, onions, carrots, and garlic is the Italian version of France's mirepoix. It is the base for this soup and is key to adding flavor. In most recipes, I suggest leaving an ingredient, like celery or onions, out if your family does not care for them. While you certainly can choose to do so, I do find this lentil soup shines best when all four ingredients are used.
• Tomatoes: I like to use a mixture of crushed and diced tomatoes for various textures. That said, feel free to use all crushed tomatoes or all diced tomatoes.
• Spices: The mixture of dried spices is the secret to the most amazing flavor in this Lentil Soup. Oregano, ground coriander, cumin, and bay leaves all combine to give this lentil soup depth and earthiness.
• Balsamic Vinegar: A key to making the flavors pop in this humble lentil soup is to finish it with balsamic vinegar. It adds a rich finish and makes the soup sing. In place of the balsamic, feel free to use the juice of one fresh lemon.

How to Make Instant Pot Lentil Soup

This lentil soup is not at all complicated to make. However, if you are new to using an Instant Pot, you may first want to check out How to Use an Instant Pot to familiarize yourself with some of the terms and steps.

• Place your lentils in a fine mesh strainer and rinse well. Dried lentils are covered in dust and dirt, so it is critical you don't skip this step. You will also want to quickly sort them to ensure no rocks or stones. Set the lentils aside to add to the soup later.
• Turn the Instant Pot to saute, add in the oil, and let it heat briefly. Once the oil is heated, add in the carrots, onions, and celery and saute for 2-3 minutes, until the celery and onion begin to soften.
• Add the rinsed lentils and garlic to the inner pot and saute for just 1 minute, then hit cancel to turn the saute function off. This will help the garlic and lentils to toast and become flavorful. You just want to be sure not to saute longer than a minute, as you don't want your garlic to burn.

• Add the broth to the inner pot, and use a wooden spoon or spatula to scrape up any browned bits on the bottom of the inner pot. This helps to prevent a burn warning.
• Stir in the crushed tomatoes, diced tomatoes, spices, and salt.

• Place the lid on the pressure cooker and be sure the vent knob is pointed to sealed. Set to cook on HIGH pressure for 15 minutes.
• Once cook time has elapsed, let the pressure release naturally. This is crucial to ensuring the lentils are fully cooked. If you try to do a quick release of pressure after pressure cooking soup, you will also be left with hot liquid spewing out of your venting knob, making a mess in your kitchen.
• Once the pressure has been fully released and the lid becomes unlocked, remove the lid. Don't be alarmed if the soup appears thick, once you stir everything, the texture will look perfect.
• Stir in the balsamic vinegar or lemon juice. everything a stir, removing the bay leaves as you come across them.

• Serve immediately. This easy lentil soup makes an easy, hearty plant-based entree especially when paired with Dutch Oven Bread and a Spinach Avocado Salad to round out the meal.

Storing Leftover Lentil Soup

Once cooled slightly, store any leftover lentil Soup in an airtight container for up to 5 days in the refrigerator. Alternatively, you can freeze lentil soup in a freezer-safe container, leaving up to 1 inch of room for expansion for up to 3 months.

More Instant Pot Vegetarian Soup Recipes

I love preparing soups using the Instant Pot. They cook up fast, yet taste as though they have been simmered for hours. Check out all of my Instant Pot Soup recipes, or browse a few vegetarian favorites below.

• Instant Pot Potato Soup
• Instant Pot Cabbage Soup
• Instant Pot Tomato Soup
• Instant Pot Pasta Fagioli
• Instant Pot Wild Rice Soup
• Instant Pot Butternut Squash Soup
• Instant Pot Vegetable Soup

This recipe was originally shared in 2019 and updated in 2023.