Instant Pot Lentil Soup is a hearty bowl of comfort. Made with tons of different vegetables, green lentils and crushed tomatoes, this easy vegan soup is sure to warm you up on a cold day! No sautéing required!
If you’re looking for more nourishing plant-based recipes, try my Instant Pot Vegan Chili!
I absolutely love lentils, but I haven’t published many recipes that use them on my website. Unfortunately, my husband can’t eat them, so testing recipes with lentils means I end up eating most of whatever I’m testing. In the case of this Instant Pot Lentil Soup, I totally didn’t mind. I’d make a batch on the weekend, then eat it for lunch all week (I 100% recommend this recipe for meal prep).
Lentils are highly nutritious and a fantastic food to include in a plant-based diet (or even if you’re not following a vegan diet). They’re a source of protein, dietary fibre, iron and folate, among other nutrients. This soup is an easy way to eat more of them!
Here’s what you’ll need to make Instant Pot Lentil Soup. See the recipe card below for exact quantities and detailed instructions.
- Yellow onion
- Sweet potato – you can double up on this to replace the yellow potato or vice versa.
- Yellow potato
- Cabbage or coleslaw mix – for added nutrition and nice texture (cabbage is a great source of dietary fibre and vitamins C and K)
- Green or brown lentils – do not use red lentils as they require a much shorter cook time. They have a mushier texture in general, which is not what we want in this soup!
- Italian seasoning
- Sugar – a small amount to offset the acidity of the tomato for a more balanced flavour
- Red pepper flakes – optional, for a bit of heat
- Vegetable broth – or sub 6 teaspoons Better Than Bouillon Vegetable Base plus 6 cups water
- Canned crushed tomatoes – thickens the soup, adding colour and flavour. I also tried it with the same amount of canned diced tomatoes, but I prefer the texture with crushed.
- Tomato paste – to enhance the tomato flavour
- Salt & pepper
- Lemon juice – to brighten the flavour after cooking
How to make it
Step one: combine the chopped ingredients and seasonings in the Instant Pot
Add the onion, garlic, carrot, celery, yellow potato, sweet potato, cabbage, lentils, Italian seasoning, sugar and red pepper flakes to the Instant Pot. Stir to combine until the vegetables are evenly distributed.
Step two: Pour in the broth and layer the remaining ingredients
Pour in the vegetable broth (or water + bouillon), then layer on the crushed tomatoes and tomato paste. Do not stir. It’s important not to stir because tomato products can cause a burn warning, if they touch the bottom of the insert during pressure cooking.
Step three: Pressure cook
Close the lid, set the vent to sealing and pressure cook on Manual High pressure for 18 minutes. Allow for a 5 minute natural pressure release, before doing a controlled quick release (see definition below) of the remaining pressure. I like to open the vent using a wooden spoon so I don’t get hit with any splatter.
Step four: Season and serve
Add a squeeze of lemon (I used about half a large lemon) and season with salt and pepper to taste. Serve with crusty bread, fresh parsley and grated parmesan, if desired.
Tips and Variations
Adjust the thickness of the soup. This soup is very hearty (and we love it this way!), but if you prefer a thinner soup, you can add more broth after pressure cooking. I suggest adding broth after cooking because the Instant Pot will take longer to come to pressure if more broth is added beforehand.
Dice your potatoes to be about the same size. This will help them cook evenly.
Do not use red lentils. As mentioned above, red lentils have a mushier texture and won’t hold their shape well in the soup. Use green or brown lentils only.
Season with salt after cooking. I purposefully didn’t add salt before cooking, because different types of broth have different amounts of salt. You can always add more salt, but you can’t take it out!
What is a controlled quick release?
A controlled quick release is when you release the pressure in “controlled” spurts, rather than flipping the vent open all at once. Controlling the release of pressure greatly reduces splatter, which can happen with dishes like pasta and soup.
How to store and reheat leftovers
To refrigerate: Transfer to a storage container(s), cool the soup completely, then place the lid on the container. Pro tip: transferring the soup into smaller/shallow containers helps it cool faster than leaving it in the pot. Refrigerate for up to 4 days. I love to make single servings for meal prep!
To freeze: Transfer to a storage container, leaving about half an inch at the top to account for expansion (the soup will expand as it freezes). Cool the soup completely, then place the lid on the container. Freeze for up to three months.
To thaw: Thaw in the refrigerator overnight or use the defrost setting on your microwave.
To reheat: for best results, reheat on the stovetop and add extra broth as necessary. Bring the soup to a rolling boil and an internal temperature of 165 °F for proper food safety. You can also reheat it in the microwave, stirring it once halfway for even heating.
More Instant Pot soup recipes
- Hearty Instant Pot Vegetable Soup
- Instant Pot Black Bean Soup (Vegan)
- Instant Pot Golden Cauliflower Soup (Vegan)
- Instant Pot Lasagna Soup
- Healthy Instant Pot Stuffed Pepper Soup
- Instant Pot Chicken Enchilada Soup
- Healthy Instant Pot Zuppa Toscana
Instant Pot Lentil Soup
- 1 medium yellow onion, diced
- 5 cloves garlic, minced
- 1 cup diced carrot
- 1 cup diced celery
- 2 cups thinly sliced cabbage or coleslaw mix
- 2 cups diced sweet potato
- 2 cups diced yellow potato
- 1 cup uncooked green lentils, rinsed
- 1 tablespoon Italian seasoning
- 1 teaspoon sugar
- ¼ teaspoon red pepper flakes (optional)
- 6 cups vegetable broth (or 6 teaspoons Better Than Bouillon Vegetable Base + 6 cups water)
- 28 oz can crushed tomatoes
- 3 tablespoons tomato paste
- sea salt and black pepper (to taste after cooking; I started with 1/2 a teaspoon of sea salt and adjusted from there)
- freshly squeezed lemon juice, to taste (about half a lemon)
- Add the onion, garlic, carrot, celery, cabbage, sweet potato, yellow potato, lentils, Italian seasoning and sugar to the Instant Pot. Mix well until the vegetables and seasoning are evenly distributed.
- Pour in the vegetable broth, then layer the crushed tomatoes and tomato paste on top. Do not stir (this will help prevent a burn warning).
- Close the lid and set the vent to sealing. Pressure cook on Manual High pressure for 18 minutes.
- At the end of cooking time, allow for a 5-minute natural pressure release, then do a controlled quick release of the remaining pressure (see note 1). I like to use a wooden spoon to open the vent to avoid getting hit with any splatter.
- Stir in the lemon juice, along with salt and pepper to taste. Serve immediately with crusty bread or a dinner roll, fresh parsley or grated parmesan. Allow leftovers to cool completely and store in a sealed container in the refrigerator. Eat within 4 days.
- A controlled quick release means letting out pressure in short bursts rather than opening the vent all at once. This helps to control splatter.
- If you prefer a thinner soup, add more broth after pressure cooking.
- Inactive time indicates the time it takes for the Instant Pot to come to pressure and release pressure.
- This recipe was tested in both 6-quart and 8-quart Instant Pot models.
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Hey, I’m Laura!
Creator of The Recipe Well
I love food and cooking, but hate doing the dishes. I use my nutrition degree to create easy, approachable recipes that will help you find your happy place in the kitchen.