Curried Red Lentil Soup

This nutrient-dense Curried Red Lentil Soup is a hearty dish that is warming and comforting with a lovely heat to it from the Thai red curry paste. Coconut milk makes it deliciously creamy and it all comes together in 30 minutes flat. Healthy, easy, and perfect for a busy weeknight!

Though somewhat cliché to start off the year with healthy soups, I think it’s exactly what we all need right now. This soup may be plant-based, but packed with hearty lentils and sweet potatoes, it makes a very satisfying dinner that will be gentle on your gut and softly warm you from the inside out.

The preparation of this curried red lentil soup couldn’t be easier, and because red lentils cook so quickly, it’s ready in a flash. Onions, fresh ginger, garlic, diced tomatoes, curry spices, and Thai red curry paste provide all the complex and aromatic flavors for the soup. Coconut milk mellows the fiery chiles in the Thai red curry paste turning the soup wonderfully fragrant and sweet.

But the secret to this rich, deeply spiced soup is roasting the sweet potatoes before adding them to the pot. Roasting caramelizes and concentrates their flavor, so they taste even sweeter.

If you wish, a few handfuls of baby spinach can be added for a little extra punch of green and iron. A drizzle of lime juice, chopped cilantro, and chopped peanuts complete the amazingly rich and exciting flavour profile of this soup. 

I like to serve the curried red lentil soup with flatbread, or mounded over basmati rice. So good!

Why You Will Love This Soup

• Budget-friendly: This hearty soup will feed a crowd and because not is meat-less it is very easy on the wallet, too.
• No bland lentil soup here! Lentils can taste bland if not flavored properly. This recipe calls for plenty of aromatics and spices to ensure the result is an outstandingly flavorful soup.
• Leftovers are fabulous: Like most lentil-based dishes, this curried red lentil soup is even better the next day.
• Vegan and gluten-free: This curried red lentil soup recipe is completely plant-based and contains no dairy or gluten.

Inspiration For This Curried Red Lentil Soup Recipe

There is a 5 star recipe with 6,000+ reviews in The New York Times for red curry lentils with sweet potatoes. It uses Thai curry paste, instead of Indian curry spices, and it is outstanding.

Also outstanding, is Ottolenghi’s curried lentil soup from his cookbook Simple. He uses Indian curry powder in his soup. I can never decide which one I like best so I borrowed my favorite things from both and ended up this one.

Admittedly, it is a little odd to mix Thai curry paste with Indian curry powder. But red lentils seem perfectly happy in both camps and this soup is incredibly flavorful because of it.

What Are Red Lentils?

Orange-pinkish in color before they are cooked, these tiny lentils are most common in Indian daal dishes. You will notice that most bags of red lentil are labeled “split red lentils”. This is because red lentils have been hulled and split which means they will break down quickly when cooked.

Once cooked, you will also notice their “red” color fades to a golden-yellow hue.

Red lentils do not need to be soaked but should be rinsed and drained before cooked. They cook much faster than all other lentil varieties and create a thick, creamy consistency in a dish.

Like all lentils, red lentils are high in protein (1 cup contains 18 grams) which makes them a great addition to a plant-based diet. Among many other healthful benefits, red lentils are also rich in fibre, a great source of iron, magnesium, and calcium.

Ingredients and Notes

I love that this curried red lentil soup is made with easy to find ingredients that are also easy on the wallet. The convenience of canned curry paste, canned tomatoes, and ready-blended curry spices, make cooking this delicious meal a breeze on a weeknight.

Here are the ingredients you’ll need:

• Red lentils – You will need 1 cup of red lentils for this recipe. See more on red lentils above.
• Sweet potatoes – I use two medium-sized sweet potatoes (about 1 – 1 1/2 pound).
• Thai red curry paste – This may be the only ingredient you don’t typically stock in your pantry. I only use the maesri brand which uses real ingredients, has no preservatives, and the flavours are truly authentic. You should be able to find it at most Asian grocery stores. This recipe calls for 3 tablespoons of the maesri red paste and I don’t find it makes the soup very spicy at all. If you’re serving it to younger kids, or you don’t like much spice, reduce the amount accordingly. Aroy-D is another brand I like but note that it is much spicier and not always vegetarian.
• Garam masala or curry powder – Though these two spice blends are not always interchangeable, for this curried red lentil soup either one will work. Garam masala is not typically spicy but if you are using a hot curry powder, use less to start. Otherwise, it could be too spicy along with the red curry paste.
• Turmeric – Delicious in all curries with awesome anti-inflammatory benefits, too.
• Onions, garlic, ginger – For the best aromatic flavour, use fresh garlic and ginger. Yellow onions or any other onions will work fine here.
• Diced tomatoes – Canned diced, or crushed, tomatoes are best for this soup. If you only have canned whole tomatoes, drain 3 or 4 from the juice and chop them up.
• Vegetable broth or water – If you have a good-quality store-bought vegetable broth, go ahead and use that. I like this one. Otherwise, water works really well here.
• Coconut milk – I prefer to use full-fat coconut milk in this vegan lentil soup. Light coconut milk will work but the soup will be a bit thinner.
• Lime juice – Optional, but adding a bright hit of acid at the end really boosts the flavour of the soup.
• Cilantro – Chopped fresh cilantro is a flavourful garnish that is fabulous in this lentil soup.
• Salt and pepper – To season.
• Baby spinach – Optional, but if you want to incorporate some greens, baby spinach is great in this soup.
• Chopped peanuts – Again, completely optional for topping but I really enjoy the flavour and bit of texture and crunch they lend to the soup.

How To Make Curried Red Lentil Soup

I like to start by roasting the sweet potato chunks which intensifies their flavour and sweetness. If you’re in a hurry, you can skip this step and simply cook the sweet potatoes in the soup.

1. Start by roasting the sweet potatoes.

• While the sweet potatoes are roasting, make the soup. In a large pot, heat a few tablespoons of olive oil over medium-high heat. Add the onions and cook, stirring occasionally, until soft and golden, 5 to 6 minutes.
• Stir in the garlic, ginger, curry paste, turmeric, and garam masala and continue to cook, stirring constantly, for about 1 minute.

• Add the lentils, broth, tomatoes, salt and pepper and give everything a good stir. Pour in the coconut milk (reserving 1/4 cup for later), stir again and bring to a boil. Lower the heat to medium-low and simmer, uncovered, stirring occasionally, for 15 minutes.

• Add the roasted sweet potatoes and cook for 3 to 4 minutes longer. Stir in the spinach and cook until just wilted, about 2 minutes. If the soup seems too thick, add a 1/4 to 1/3 cup of water.

• Remove from heat and stir in the lime juice. Taste and adjust seasoning with a pinch of salt, if needed. Serve in bowls drizzled with the reserved coconut milk, and garnish with chopped cilantro and chopped peanuts, if using.

Tips To Make A Great Curried Red Lentil Soup

• Roast the sweet potatoes. This extra step is really worthwhile. Roasting the sweet potatoes really intensifies their sweetness and because they are added at the end, they don’t get mushy.
• Use relatively fresh lentils. Though lentils last really long, if they are too old they will not soften when cooked. I try not to keep an open bag of lentils longer than 6 to 8 months.
• Rinse the lentils. Lentils should be rinsed in case they are dusty or have bits of dirt. Rinsing also helps reduce foaming.
• Don’t cook red lentils on high heat. Red lentils cook really fast and high heat will turn them mushy in an instant. I don’t mind the creamy texture of overcooked red lentils but they really are best when they retain a bit of a bite.
• Adjust the heat level to your taste. Curry pastes, and curry spice blends, will vary greatly in heat level depending on the brand. Start will less and add more as you go.
• Double the recipe for leftovers. This curried red lentil soup gets more delicious every day which makes it great for meal prep. Double the recipe and you’ll enjoy the most amazing lunches for days.

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