Kale Lentil Soup (Stew): Hearty, Healthy, Vegan

I’m sitting down to start this post on the Winter Solstice, and I can’t think of a more fitting time to enjoy a bowl of filling, soul-warming, hearty kale lentil soup. (But you know me: I say it’s always soup season.) This kale lentil soup recipe is naturally vegan and loaded with flavor, nutrients, protein, fiber, and love. It’s easy to make and freezer-friendly too! We always make a double-batch and freeze the extras for easy future meals. I hope you enjoy our extra-nutritious take on a classic lentil soup – with plenty of kale! 

Before we get going, I should note that our our homemade kale lentil soup recipe is quite thick. So much so, that is borders on becoming lentil stew! Yet it’s easy to adjust the consistency to be exactly how you like it, described more below.

What type of lentils are best to make lentil soup?

Green, brown, red, yellow… You can use any kind of lentil to make homemade lentil soup. They’re all incredibly nutritious and delicious! One of the key differences is their cooking time, so plan and adjust accordingly. Yellow and red lentils cook the fastest (within 15 minutes or so) but also have the tendency to get mushy or fall apart. 

This hearty kale lentil soup recipe calls for green lentils. Brown and green lentils are often used interchangeably and take a little longer to cook, from 25 to 45 minutes. Both brown and green lentils hold their shape better than yellow or red. 

Do I have to soak the lentils before making kale lentil soup?

Nope! That is one of the beautiful things about lentils. Unlike dry beans, lentils do not need to be soaked in water for hours before cooking them. Instead, it is recommended to rinse and sift lentils in a strainer under water before use. This gives you the opportunity to wash away any dirt, dust, or other debris (e.g. small rocks) that may be present. 

However, you certainly can soak lentils in water before cooking them if your schedule allows. Soaking lentils in water for an hour or so will reduce the cooking time by about half. More importantly, there are some added health benefits to soaking lentils and other legumes. 

Lentils (along with most seeds, grains, nuts and legumes) contain a plant-based compound called phytic acid. Because phytic acid naturally inhibits the absorption of important minerals like iron, zinc and calcium, it is often referred to as an “anti-nutrient”. Yet when lentils are soaked for 8 hours or longer, a number of enzyme reactions occur and the phytic acid content is greatly reduced. The resulting lentils are more nutritious, easier to digest, and may also cause less gas and bloating. 

Why lentil soup is so good for your health

Lentils, a member of the legume family, are one of the most nutrient-dense plant-based proteins around. In fact, when comparing protein content per serving against all the other beans and legumes out there, lentils rank number 2 (soybeans are number 1). In addition to protein, lentils offer high levels of fiber, calcium, iron, potassium, and folate, but are low in fat. Nutrition experts consider green lentils the most healthy of them all. 

Lentils contain all nine essential amino acids (albeit low levels of methionine). So, when paired with whole grains such as barley, brown rice, quinoa, or whole-wheat bread, it’s considered a “complete protein” – providing a high-quality but more heart-healthy source of protein than meat. That is one reason we love to serve our kale lentil soup with a slice of homemade sourdough bread made with whole grains.

And that’s not even getting into the other ingredients that are in this kale lentil soup recipe. Carrots, celery, onion, garlic, spices… all great for your health! Plus, did you know that kale is considered a superfood? Kale is incredibly rich in vitamins, minerals, antioxidants, fiber, and even contains omega-3 fatty acids. So can I get a #eatyourgreens?

How to Make Homemade Kale Lentil Soup

Ingredients

The recipe below makes about 2 to 3 quarts of soup. Use the printable recipe at the end of this article to adjust the servings and easily scale up or down as desired!

• 2 Tbsp olive oil or butter 
• 1 large yellow or white onion, diced
• 4 cloves of garlic, peeled and finely diced
• 2 celery sticks, diced
• 2 large carrots, diced
• 2 cups of dry green lentils
• 1 quart (4 cups) of vegetable broth. Learn how to make homemade broth from saved veggie scraps here!
• ½ cup to 1 cup water (adjust based on personal preference for final soup consistency)
• 1 can (14 oz) of crushed tomatoes
• 1 tsp paprika. Want to change things up? Try this kale lentil soup recipe with smoked paprika instead! It’s excellent both ways.
• ½ tsp sea salt (more to taste, if needed)
• ½ tsp cumin
• ½ tsp coriander
• 1/4 tsp garlic powder (optional)
• black pepper, to taste
• 2 bay leaves, fresh or dry
• 1 bunch of kale. Use any variety of kale you prefer: lacinato or “dino” kale, curly green kale, or others.
• 1 lemon (to juice) OR 1 tsp of red wine vinegar

Instructions

1. Wash and chop or dice the onions, garlic, celery and carrots into small pieces. 
2. Add a couple tablespoons of olive oil (or butter/vegan butter) to your soup pot, and then add the chopped onions, garlic, celery, and carrot along with the bay leaves and sprinkle of salt and pepper.
3. Saute the onion, carrots, celery and garlic over medium heat for about 10 minutes, until everything starts to soften. Stir occasionally. Don’t rush this part! It’s where much of the flavor for the kale lentil soup is developed. 
4. Meanwhile, rinse and sift the lentils under water in a colander.
5. Add all the remaining called-for ingredients to the pot (broth, lentils, tomatoes, and spices) EXCEPT for the kale and lemon or vinegar.
6. Bring the mixture to a boil, then reduce to a simmer.
7. Cover the pot and allow everything to simmer for 25-40 minutes, until the lentils are cooked and softened to your desired texture. Some folks prefer lentils on the el dente side, or cooked longer for a softer, creamier consistency. Stir occasionally. (Less time if you pre-soaked the lentils).
8. De-stem the kale and roughly chop or tear the leaves into bite-size pieces.
9. Then add the kale to the soup, stir, cover the pot again, and continue to cook for 5 minutes.
10. Remove the finished kale lentil soup from the heat before adding your lemon or vinegar. The pop of acid really brightens the soup and brings all the flavors together! Either squeeze the juice of one lemon into the soup, or add 1 tsp of red wine vinegar.  
11. Taste and add more salt and pepper if desired. 
12. Finally, serve and enjoy! Kale lentil soup is amazing with a side of whole grain bread, topped with parmesan cheese, or simply served as-is. Get our homemade sourdough bread recipe here.

Note:

To adjust the consistency of the soup, feel free to add more water or broth. Or for a thicker, extra-creamy soup, you can blend a small portion (a cup or two) of the finished soup and add it back in – or give it a couple blitzs with an immersion blender. 

How long does kale lentil soup stay good for?

Homemade kale lentil soup is good for about 5 to 7 days in the refrigerator. Store soup in an air-tight container with a lid for maximum freshness. Or, freeze your leftover soup to enjoy for many months to come! Frozen homemade lentil soup is good for up to a year in the freezer, though it will be the best quality within 6 months. 

Freezing kale lentil soup

We always keep our freezer stocked with homemade soup – and kale lentil soup is no exception! We use our favorite durable, reusable BPA-free quart freezer containers. They’re the perfect size for soup for two! Fill containers all the way to the “fill line” near the top. The less air inside the container, the less chances of freezer burn.

For the best quality and food safety, allow the soup to fully and rapidly cool before putting it in the freezer. To do so, we either: 1) allow the pot to cool at room temperature for about an hour and then submerge it in an ice bath in the sink for a couple hours (stirring frequently), refrigerate the pot without the lid overnight, and then package it in the morning. Or 2) allow the pot to cool at room temp for no more than a couple hours (stirring frequently) and then break up the room temperature soup into several quart storage containers to cool in the refrigerator overnight with the lids off (spread the containers out so they’re not crammed together).

Defrost frozen kale lentil soup in the refrigerator the day before use, or on the countertop for a few hours.

Bon appétit!

Alright friends, now it’s time to get cooking! All in all, we hope you love our hearty, healthy kale lentil soup recipe just as much as we do. Once you give it a try, please stop back by to leave a review! May your bellies be warm, full, and satisfied. And if you’re looking for even more tasty vegan soup recipes, don’t miss the list below!

• Creamy Roasted Tomato Basil Soup
• Creamy Potato Leek Soup
• How to Make Vegetable Broth from Saved Kitchen Scraps
• No-Chicken Noodle Soup
• Creamy Roasted Carrot and Sweet Potato Soup 
• Butternut Squash and Sage Soup