Sunday, January 06, 2013

Slow Cooker Recipe for Vegetarian Greek Lentil Soup with Tomatoes, Spinach, and Feta

Slow Cooker Greek Lentil Soup
Delicious vegetarian lentil soup with Greek flavors and a sprinkling of Feta!

How about an ultra-tasty lentil soup for A Month of Daily Phase One Recipes?  I've been a lover of lentils for quite a few years now so there are many variations of Lentil Soup on my blog, but when I spotted a recipe for Greek Lentils with spinach and Feta in the American Heart Association Healthy Slow Cooker Cookbook, I couldn't resist turning it into a soup.  And since lentils are a limited food for Phase One, I added other ingredients like celery, tomatoes, and lots of stock so I could have a larger serving.  This slow cooker recipe starts with just lentils, chopped celery and onion, garlic, vegetable or chicken stock, canned tomatoes, and spices, and if you chop the vegetables the night before it's easy to throw in the slow cooker in the morning and let it cook all day.  When you get home, add chopped spinach to the soup with some lemon juice and cook a bit longer, then scoop into bowls, add Feta, and you have a tummy-warming soup for dinner.   I've never used Feta as a soup topper before, but I loved how it added a vibrant burst of flavor. 

Of course this delicious Phase One soup is my Meatless Monday recipe for this week.  Finding good vegetarian recipes for Phase One can be a challenge, but Jake and I both gave this soup two thumbs up when we tested the recipe.  If you're a vegetarian who's doing Phase One, check the archives page for Phase One Vegetarian Recipes, where dishes that are vegan are marked with a (v).  (This recipe could easily be vegan by using vegetable stock and skipping the feta.)

Start with 2 cups regular brown lentils.  (Lentils that are fresher will cook more quickly, so take that into account when you're timing the soup.)

You'll also need 1 medium onion, chopped small, and 1 cup of celery, also chopped fairly small.  (Do this the night before if you want to get this in the slow cooker early in the morning!)

Put the lentils, onions, celery, vegetable or chicken stock, Greek Seasoning, dried thyme, dried oregano, minced garlic, black pepper, and canned tomatoes with juice into the slow cooker and cook on high for about 4 hours or on low for 8-9 hours, until the lentils are as soft as you prefer.  (Slightly longer cooking time won't matter much, either on high or low.)

Here's how the soup looked after we cooked it nearly 4 hours on high.  The lentils were soft but still kept their shape.

When the lentils are softened to your liking, chop the spinach (and wash in salad spinner if needed.)

Add the chopped spinach to the soup with the lemon juice, turn to high if cooking on low, and cook on high for 30 minutes more.  (Add a little more stock at this point if the soup seems thicker than you'd like.)

When the spinach is nicely softened, serve soup hot, with a tablespoon or two of crumbled Feta on top of each bowl if desired.

Slow Cooker Vegetarian Greek Lentil Soup with Tomatoes, Spinach, and Feta
(Makes about 8 servings; recipe inspired by Greek Lentils in the American Heart Association Healthy Slow Cooker Cookbook.)

2 cups brown lentils (washed and picked over if needed)
8 cups vegetable or chicken stock (or more)
1 medium onion, diced small
1 cup chopped celery, chopped into fairly small pieces
1 T Greek Seasoning (I use The Spice House Greektown Billygoat Seasoning, but there are a few good brands.)
1 tsp. dried thyme
2 tsp. dried oregano (preferably Greek or Turkish oregano)
1 T minced garlic
fresh-ground black pepper to taste
1 can (14.5 oz.) petite diced tomatoes with juice
1 bunch spinach leaves, stems cut off, chopped and washed
2 T fresh-squeezed lemon juice (or a little less if you're not that into lemon)
crumbled Feta Cheese for serving (optional, but good)

I used this Crock-Pot 5-Quart Programmable Smart-Pot Slow Cooker for this recipe. (A slightly smaller model would also work.)  If you're going to cook all day, this type of slow cooker is a good choice because you can set it to cook for 8 hours on low and then it switches to "warm" after 8 hours.

Chop onions and celery and measure 2 cups brown lentils.  (Do this the night before and store in the fridge in a Ziploc bag if you want to get this into the slow cooker quickly in the morning.)  

Put the lentils, onions, celery, vegetable or chicken stock, Greek Seasoning, dried thyme, dried oregano, minced garlic, black pepper, and canned tomatoes with juice into the slow cooker.  Cook on high for about 4 hours or on low for 8-9 hours, or until the lentils are as softened as you'd like them.  (Cooking time will partly depend on how fresh your lentils are; lentils that have been on the pantry or store shelf for a while will take a little longer to cook.)

When the lentils are softened as much as you'd like, chop the spinach and wash in salad spinner if needed.  Add spinach and lemon juice to the soup, turn slow cooker to high if you were cooking on low, and cook about 30 minutes more.  (A little longer won't hurt, but the longer you cook the spinach the darker green it will get.  Add another cup or two of stock at this point if the soup seems thicker than you'd like.)  Serve soup hot, with a tablespoon or two of crumbled Feta sprinkled on each serving if desired.

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South Beach Suggestions:
Low-glycemic dried beans or lentils are approved for all phases of the South Beach Diet, but portion size is limited for Phase One.  In a soup like this with stock, tomatoes, onions, celery, and spinach in addition to the lentils you can have a little more, but I would still eat a fairly small bowl of this with a moderate amount of Feta for Phase One, with something like a big green salad on the side.  

Nutritional Information?
I chose the South Beach Diet to manage my weight partly so I wouldn't have to count calories, carbs, points, or fat grams, but if you want nutritional information for a recipe, I recommend entering the recipe into Calorie Count, which will calculate it for you.

More Meatless Lentil Soups You Might Like:
(Recipes from other blogs not always South Beach Diet friendly; check ingredients.)
Syrian Vegetarian Red Lentil Soup ~ Herbivoracious
Mexican Red Lentil Stew with Lime and Cilantro ~ Kalyn's Kitchen
Greek Lentil Soup ~ Healthy Greek Kitchen
Vegetarian Lentil Soup with Spinach, Tomatoes, and Cumin ~ Kalyn's Kitchen
Roasted Red Pepper, Lentil, and Spinach Soup ~ Albion Cooks   
(Want even more recipes? I find these recipes from other blogs using Food Blog Search.)

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Posts may include links to my affiliate account at, and this blog earns a few cents on the dollar if readers purchase the items I recommend, so thanks for supporting my blog when you shop at Amazon!

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  1. Yes, I would love this soup (and made easy in the slow cooker, even better!). I made a Greek lentil soup with lemon, and I think it's the first time I combined those two ingredients in a soup. The flavor burst was a revelation. Can't wait to try your recipe.

  2. Lydia, it was so good. The lemon + Feta really makes the soup!

  3. I know that this is a soup I would absolutely love! The Greek flavors sound so good to me!

  4. Carrian, it made me wonder why I had never thought of it, it was so good!

  5. I usually always have strong Cheddar in my fridge and so quite often grate that on top of vegetable soups, which nearly always include brown lentils. Never tried it with feta though, so will now have a go.

  6. Rachel, the Feta really perked up this soup.

  7. So funny - I just picked up some lentil soup the other day for my son from a local Greek restaurant and he loved it so I made a pot this morning using a recipe from my friend's Greek cookbook. From what I've been reading, wine vinegar is essential to add just before serving, but I love the idea of some fresh lemon juice to perk up the flavors too. I also love the idea of adding spinach to it and serving it with feta. Am thinking of making this for the soup class I'm teaching at our local senior center later this month. Happy New Year Kalyn!

  8. Jeanette, we are channeling each other I guess. And how fun that you're doing a soup class again!

  9. Leave it to you to pack lentil soup with amazing flavors. Cant's WAIT to try this . . . tomorrow!

  10. Donna, hope you like it as much as we did!

  11. Oh my! What a great idea! I am definitely making this!

  12. Kalyn..I recently found a jar (19 oz.) of cooked lentils (in water) and bought them, not having a clue what to do with them. :) Lo and behold now I do. Since they are already cooked I'll just have to make a couple of cooking changes and the soup be great. Thanks for another great recipe.


  13. Sounds like a winner. I'm always looking for interesting things to do with lentils, and once more, you've come up with great flavor combinations. Look forward to trying it. Tomatoes, lemon, feta, greek seasonings - How can it not be delicious???

  14. This is pretty good! I planned on 4 hours on high, but after 3, I didn't think it'd be done enough to my liking. So I ended up putting it all in a pot on the stove and simmered for the last hour. I also pureed about half of it with an immersion blender before adding the spinach. I couldn't find greek seasoning either, so I used a little extra oregano and thyme plus some garlic powder, onion powder, red pepper flakes, and ground marjoram.

  15. Sarah, glad you like it. If the lentils have been sitting on the pantry or store shelf for a while, they take longer to cook, but fresh lentils should easily be done in 4 hours in the slow cooker.

  16. Yum! I made this last week, and it was a nice change from my "routine lentil" soup~ Thanks!

  17. Thanks a lot, this is in our slow cooker now, slightly scaled down since our family has two preschoolers. Was pleased to find something else for lentils and tomato soup than a lentil chili, and as a bonus my celery has a place to go. I tossed in a carrot and some frozen peas since we have an abundance of both. Thanks--from Katharine in Brussels, who's using her husband's account :)

  18. Katharine, this is a recipe I've made several times for parties; hope you enjoy!

  19. Hi Kalyn, we've jsut tried it and "wow" is the verdict! Even my picky preschoolers! Thanks.

  20. We have made your wonderful soup again, and this time my son asked me to leave the tomatoes out (he's 3...). It's still delicious! Truly a great recipe. Thanks.

    1. Thanks Katharine! And that's very cute that your 3 year old has such opinions about how food is prepared, love it!

  21. This soup is INSANELY good! I cannot stop eating it. Thank you so so sooooo much for the recipe. There is a small chain in the northeast called Aladdin's that makes an amazing lentil soup. My husband and I are currently in south Texas with no sign of a good Mediterranean restaurant (or any good/healthy restaurant, in general). I calculated the nutrition info with 1/2 cup reduced fat feta for 8 servings and is as follows: 128 calories (!!!!!!), 2.2 g fat, 5 mg cholesterol, 902 mg sodium, 20 g carbs, 6 g fiber, 5 g sugar, 9 g protein. I am currently posting it to my Instagram feed it was THAT good!


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