Slow Cooker Winter Vegetable Soup with Split Red Lentils
Hearty slow cooker winter vegetable soup with split red lentils. This healthy crock pot recipe is packed with vegetables, red split lentils, and finished with a drizzle of olive oil, chopped parsley, and parmigiano-reggiano cheese.

Today marks a big day! This slow cooker winter vegetable soup with split red lentils is the first crock pot soup recipe to ever grace the blog. Healthy vegetable soups are my jam. Cue the confetti and break out the crock pots!
A bunch of you have been asking (for some time now) that I share slow cooker recipes and while I always want to oblige any recipe requests that you throw my way, I didn’t actually own a slow cooker machine until about six months ago.
It is probably the one kitchen appliance that I’ve held out on over the years.

Can I confess something? For a long time, I didn’t quite get what all of the fuss was about. Feel free to hate me a little bit.
I’m an adamant believer in sauteing and browning (hello flavor!) and felt like I would be betraying my favorite Dutch oven, because I’m weird like that.
On the other hand, the idea of throwing everything into a slow cooker in the morning, leaving the house if need be, and coming back to a fully prepared dinner was incredibly appealing. Who wouldn’t love that?! The good news? You can get slow cookers with stovetop-safe inserts, which allow you to enjoy the best of both worlds.
This soup can be prepared two ways: you can either choose to saute the onions beforehand (which will help maximize their flavor) or you can just throw them into the slow cooker with the remaining ingredients, turn the machine on, and walk away. I’ve tried it both ways and the soup still comes out great.


This soup is all about the vegetables and it is packed with them.
Onions, celery, carrot, zucchini, chopped canned tomatoes, and finely thinly sliced savoy cabbage. Yukon gold potatoes are added as well (no peeling required) to help bulk it up just a bit. My mom actually made a very similar soup for us when we were growing up, and I always loved it.
Hearty and extremely filling, yet you don’t feel weighed down at all. It’s the perfect soup to enjoy on a cold and dreary winter day – especially if you have access to good crusty loaf of bread.

One important tip that I realized after testing this recipe a few times was the importance of fresh (or at least, as fresh as possible!) split red lentils.
Yes, all lentils at the store are dried. But if you’ve been hanging onto a mason jar full of split red lentils for, um, maybe a year – I blame the move – please don’t use those for this.
Older lentils tend to dry out even further and will take significantly longer to cook and become tender. Try to find a fresh bag of them at the grocery store or choose them from a bulk bin that gets refreshed often (i.e. not the bag of lentils that has been sitting in your convenience store for three years on the top shelf).
I love split red lentils, because they are delicate and small, yet break down in the cooking process and help thicken the soup. They also are incredibly good for you and contain lots of fiber and protein.

Don’t forget to finish the soup by drizzling it with a touch of olive oil, sprinkled parsley, and a generous pile of freshly grated parmigiano-reggiano cheese.
It’s the final important touch.

Slow Cooker Winter Vegetable Soup with Split Red Lentils
Equipment
Ingredients
- 2 tablespoons extra virgin olive oil
- 1 large yellow onion diced
- 3 celery stalks diced
- 3 medium carrots trimmed, peeled, and diced
- 2 medium zucchini ends trimmed and chopped into ¾-inch chunks
- 3 small Yukon gold potatoes scrubbed and chopped into ¾-inch cubes
- ¾ cup split red lentils
- 1 cup (240 mL) canned chopped tomatoes with their juices
- 2 pieces of parmigiano-reggiano rind
- 2 dried bay leaves
- 3-4 sprigs of fresh thyme
- 5 cups low-sodium chicken stock or vegetable broth
- 1 teaspoon kosher salt plus more to taste
- freshly ground black pepper
- 2-3 cups finely sliced savoy cabbage reserved for later
For Serving:
- extra virgin olive oil for drizzling
- freshly chopped flat-leaf parsley or basil, for garnishing
- freshly grated parmigiano-reggiano cheese
Instructions
- If you own a stovetop-safe slow cooker insert: Heat the olive oil in the insert over medium heat on the stove. Add the onion and celery and saute until tender, 5 to 7 minutes, before transferring to the slow cooker and continuing with the instructions below.
- If you do not own a slow cooker with a stovetop-safe insert (or wish to skip step one): Place the insert on the slow-cooker base (this recipe will fit a 4-quart capacity slow cooker). Add the olive oil, onion, celery, carrot, zucchini, potatoes, split red lentils, chopped tomatoes, parmigiano rind, bay leaves, thyme, chicken stock, kosher salt, and black pepper. Stir together. Cook on the high heat setting for 4 to 6 hours, or until the red lentils are tender (or alternatively, cook on the low heat setting for 8-10 hours).
- In the last hour of cook time (or 2 hours, if you are cooking over the low heat setting), add the thinly sliced cabbage. Remove and discard the dried bay leaves, parmesan rinds, and any tough thyme sprigs. Adjust the seasoning to taste salt and pepper – you will most likely need to be liberal on the salt for this soup.
- Serve the soup and top each serving with a drizzle of extra virgin olive oil, a sprinkling of freshly chopped parsley, and freshly grated parmigiano-reggiano cheese.
Tips for Success:
- Older lentils tend to dry out and might take significantly longer to cook. Try to find a bag at the grocery store or choose them from a bulk bin that gets refreshed often (i.e. not the bag of lentils that has been sitting in your convenience store for three years on the top shelf).

124 Comments on “Slow Cooker Winter Vegetable Soup with Split Red Lentils”
Just made this soup during the blizzard here in NY. Cannot wait to have it for dinner!!! My whole apartment smells amazing from this soup. Thanks!!
Yay! Soup is perfect blizzard food. Hope you’re not snowed in! Hope you liked the soup too! Thanks so much for commenting!
What if I am unable to come up with a rind of the Parm Reg? Can I substitute shredded while it cooks and if so how much and when should I add it?
You definitely don’t have to add parmigiana rind to the soup! I just have a habit of doing so, because I generally have a few in my fridge and it adds good flavor to soup. You can just leave it out completely. I wouldn’t add shredded cheese to the soup as it cooks, and just top it with a bit more when serving if you feel like it! Hope this helps.
How to adjust for whole red lentils?
Made this last night and did use vegetable stock since I’m a vegetarian along with 2 cans of stewed tomatoes in place of the chopped, because I love stewed. It was delicious!
this looks delicious! i have 2 questions– can this be made over the stove without a slow cooker, just adjusting the cook time? and it says serves 4-6… i have 4 people to feed for a party, is this enough for like really big bowls of soup? thanks!!
I love vegetable soups too! I just made this on the stove top because I didn’t plan ahead, and it was delicious! Thanks for the recipe. Love your website!
So happy to hear that! Thank you so much Katie!
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Hi, will vege stock still work well?
Sorry for only just getting back to this! Vegetable stock would definitely work – I don’t tend to love store-bought veggie stocks, but that’s just my own personal preference. Hope this helps!
Made this soup last night and it is so so tasty! I’m on a health kick so I swapped the potatoes for pumpkin and left out the Parmesan – and it still turned out amazing. I will be making this again and again. Thank you!
I really like the potatoes, because they help make the soup a bit more filling and hearty. But I think you could substitute with butternut squash or other root vegetables? It would change the flavor of the soup a bit, but should work fine!
This soup is delicious! It’s easy to make and full of healthy veggies. The olive oil, Parmesan, and parsley topping put it over the top.
This soup looks and sounds wonderful. Beautiful photos.
You have such delicious recipes and a great site!
I’m so weird with lentils. I’m always looking for a recipe that I actually enjoy them in!! This soup looks delish and like an absolute must-make!
Give me a big bowl!!
Looks sooo cozy. Red lentils are my favorite, and I love the color! Andrew just got a slow cooker and this would be a great recipe to try out. Can I also mention how GORGEOUS your photography is? I love those bowls with those clean black lines around the rim!
Thank you SO much Erica! They are ceramic bowls that I got from this cool shop in Berkeley, CA. I love them too! 🙂
Which slow cooker do you have? I don’t have a 4 quart, only 6 quarts (two of them!) and am thinking I need a smaller one for variety. As if I need yet another kitchen appliance. GAH!
I know we already discussed this – but I wanted to reply directly to the commment too, in case its helpful for others! I have this one: http://www.williams-sonoma.com/products/all-clad-cast-aluminum-slow-cooker/
Totally digging this soup! It is definitely the time of year for a good crockpot meal. I’m so happy you shared this as your first one with us 🙂
I perfect soup to have at this time of the year! Healthy and warm and nurturing! Getting us all ready for the serious eating later in the month! Yum! I wish I had a bowl of this right now! I had no idea about the lentils aging and drying out! Thanks for the tip, Laura!
This is just what I need!! it is freezing here today and this looks perfect! 🙂
Thank you Tieghan!
Potatoes add a lot of filling and heartiness to the soup, so I like them a lot. Perhaps butternut squash or some other root vegetable could be substituted? The soup’s flavor would be a bit different, but it would still be delicious! you can also check https://organiselife.com.au/
Girl, I own 2 slow cookers 😉 Although I don’t use them that much and I’ve never made soup in it! Usually just chicken (and this year I finally made applesauce!)
Haha!!! It’s been really fun to put my slow cooker to use over the past few months. I have to say, it does put dinner on the table quickly 🙂