Red Lentil and Sweet Potato Soup

Who knew? - Melissa Clark’s Red Lentil Soup was the most reviewed recipe on the New York Times website as of last November. She had gotten the recipe from a friend and just like the rest of us, adjusted some things according to what she had in the house. When I made it, I made a few changes too and I think I ended up with one of the best soups I’ve ever made…OR had! 

Jump to My Red Lentil and Sweet Potato Soup

A few main changes:

I added a diced sweet potato, which melded perfectly with the color of the red lentils and made a beautiful, rich, slightly sweet soup.

I cooked the onions as I usually do, until they are soft, soft, SOFT. I don't add spices or any liquid ingredients until the onions have given up any signs of resistance and are left sweet and almost buttery.

I also added a lot more cumin AND chili powder and cooked them as I usually do on low, low, LOW for 3 (not two) minutes.

Then I added the tomatoes, lentils and finally the stock.

  

Other little changes: I pureed half the soup at first…as in the original recipe. But I thought the red lentils had a slightly gritty consistency, so I pureed the whole thing. Really good move.

I always add red wine vinegar to my lentil soup and to my chili too, so I did that here as well, instead of the lemon juice.

Instead of tomato paste, use any tomatoes you have on hand - plum, beefsteak or other. And now that I’m thinking about it, if you want to sub a large can of tomatoes for some of the stock, go ahead! 

My version of this recipe includes two techniques that I use almost every day - sweating the onions until they’re completely soft and cooking the warm spices over low heat before any liquid is added. That gets rid of the raw taste and starts to develop the wonderful toasty flavors of the spices. 

The only thing I’d change? I wish I’d made double the recipe to ensure there was some in the freezer… 

My Red Lentil and Sweet Potato Soup 

(serves 6-8)

2 big onions, chopped

2 tbls. of olive oil (more if necessary)
Large pinch of Kosher salt

3 carrots, peeled and chopped
1 sweet potato, peeled and chopped
2 tsps. cumin
2 tsps. chili powder
Freshly ground black pepper
2 quarts vegetable stock
2 tomatoes, chopped
OR 1 quart vegetable stock and 1 large can (28 oz.) crushed or diced tomatoes  

1 cup red lentils
1 tbl. red wine vinegar   

In a large pot over medium high heat, stir onions in olive oil until you hear a sizzle. Stir in large pinch of salt. Turn down heat to medium-low. Cover and cook for 10 minutes until onions are softening nicely. Stir in carrots with another pinch of salt. Cover and continue cooking on low heat until the onions are completely soft, at least another 10 or 15 minutes. (Don’t worry about the texture of the carrots.) 

Stir in sweet potato with cumin, chili powder and black pepper and stir over low heat for 3 minutes to cook the spices. 

Add stock, tomatoes and red lentils. Bring to a simmer. Stir in red wine vinegar and cook, covered, until the lentils are soft, about 40 minutes. Taste for seasoning. 

Puree in batches in a blender until smooth. Or use an immersion blender, which will give you a slightly coarser soup. Serve immediately or cool and freeze.