Easy Thai-Inspired Vegan Sweet Potato Soup Recipe

Name: Sweet Potato Soup Recipe
Prep time: 20 min
Cook time: 30 min
Total time: 50 min
Cuisine: Thai
Ingredients: 2 large shallots, diced (or sub one onion); 2 tablespoons olive oil; 6 cloves garlic, chopped; ¼ cup finely chopped lemongrass (packed) 2-3 stalks (or use lemongrass paste in a tube); 1 tablespoon ginger, finely chopped (or ginger paste); 1 small Serrano chili (or jalapeno for less spicy), split in half (stem intact); 1 teaspoon yellow curry powder; ½ teaspoon turmeric; 4 cups veggie stock; 1 cup water (use as needed, wait to add until blending); 1 teaspoon salt; 2 lbs yams, peeled, cubed into one-inch cubes (feel free to sub some with carrots); ½ cup to 1 cup coconut milk- add to color.; 2 teaspoons brown sugar; 2 teaspoons soy sauce; 1-2 tablespoons lime juice; salt and black pepper to taste

A healthy, Thai-inspired Sweet Potato Soup made with lemongrass, ginger, lime, and coconut milk. Creamy, comforting, flavorful-and fully vegan and gluten-free.

bowl of sweet potato soup with coconut milk, lime slices, cilantro, and scallions.

We are kept from our goal, not by our obstacles, but by a clear path to a lesser goal. ~ Robert Brult

This Sweet Potato Soup is one I return to again and again. Infused with ginger, lemongrass, coconut milk and a bright lift of lime, it carries the aromatic flavors I fell in love with while traveling through Thailand. Warm, vibrant, and deeply soothing, it's a bowl that feels both uplifting and grounding.

Over the years, I've learned that some of the most comforting dishes come from the simplest ingredients, and this soup is a beautiful example of that. Sweet potatoes (yams) lend their natural sweetness and velvety texture, while ginger, lemongrass, shallot, and garlic build lively depth. A squeeze of lime adds brightness, and a light touch of coconut milk brings gentle creaminess without making it heavy.

Why you’ll love this Sweet Potato Soup Recipe

Not only is this soup vegan and gluten-free, but it’s also so flavorful, healthy, and light, bringing a little sunshine to your life. Guaranteed!

It can be made ahead on Sunday for the busy workweek and reheated for lunch or dinner! Perfect for a chilly day!

Why I Use Thai Ingredients in Sweet Potato Soup

I chose Thai-inspired flavors for this soup because they naturally create the perfect balance of sweet, spicy, sour, and savory. These flavors are also deeply comforting and nourishing, making the dish feel both cozy and refreshing.

Ingredients

Sweet potatoes (yams): If desired, you can substitute some of the chopped potatoes with carrots to mix it up!
Shallots, garlic cloves, lemongrass, and ginger: Gives the soup a fragrant, aromatic base. Sub an onion for the shallot if desired. Use fresh lemongrass and ginger if you can find it, or substitute with lemongrass paste and ginger paste.
Serrano chili: Or use a jalapeño for slightly less heat. Split the chili in half, leaving the stem intact (this makes it easy to remove before blending).
Yellow curry powder and turmeric: For deep, savory flavor and to enhance the vibrant color of the soup.
Vegetable stock: Use our homemade vegetable broth for the best flavor, or use store-bought.
Coconut milk: Gives the soup a creamy, smooth texture. The amount can be adjusted as desired. I keep it on the lighter side.
Brown sugar: For a hint of sweetness that balances the soup.
Soy sauce: For umami flavor. The saltiness helps enhance the other flavors in the soup. If not vegan or vegetarian, you can also use fish sauce.
Lime juice: For fresh, vibrant flavor with a hint of tanginess.
Garnishes: Cilantro, a swirl of coconut milk, scallions, sriracha, lime wedges, and Aleppo chili flakes or red pepper flakes.

How to Make Sweet Potato Soup

1. Sauté the aromatics. Add olive oil to a large pot and heat over medium. You can use coconut oil for a subtle, sweet, nutty flavor, if preferred. Add shallot (or onion) and sauté for 2 minutes, stirring. Add ginger, lemongrass, and the whole, split chili. Sauté for 3-5 minutes, stirring continuously. Add yellow curry powder and turmeric and stir for 1-2 minutes.

2. Simmer the soup. Add vegetable stock, water, and salt. Scrape the sides of the pot, stirring all the veggies, and stir. Bring to a simmer, then add the sweet potatoes. Cover the pot with a lid and simmer over medium-low heat for 15-20 minutes, or until the sweet potatoes are fork-tender. Turn off the heat and prep the garnishes.

diced one-inch sweet potato cubes on wood butcher block.

large dutch oven with sweet potato soup broth with serrano chili in the center, cut in half, stem intact.

3. Purée the soup. It’s nice to let the soup cool a little before transferring it to a high-powered blender to avoid burning your hands. Remove the chili before blending. Blend until silky smooth. An immersion blender or stick blender works for this, too. If using a blender, return the soup to the pot. Gently warm over medium-low heat.

large dutch oven with uncooked sweet potato added with broth and serrano chili.

large dutch oven with immersion blender puréing sweet potato soup.

4. Season, taste, and adjust. Stir the coconut milk into the soup. Start with 1/2 cup, then add up to 1 cup, depending on texture preference. Save a little to swirl on top as a garnish. Add the brown sugar, soy sauce (or fish sauce), and lime juice. Taste and adjust, adding more soy sauce for depth, a pinch or two of salt to enhance flavor, more lime for tanginess and acidity, more sugar for sweetness, or sriracha for heat.

large dutch oven with creamy sweet potato soup with wood spoon swirling in coconut milk.

5. Garnish and serve. Ladle soup into bowls and add a swirl of coconut milk to each. Sprinkle with cilantro and scallions and top with lime wedges and Aleppo pepper. If the coconut milk is too thick, add a little warm water to thin it out.

bowl of sweet potato soup with coconut milk, cilantro, green onions, and lime.

Chef’s Tips

Balance the flavors. This soup has a balance of salt, sweet, sour, and spice. The secret to perfecting the flavor balance is to taste and adjust until you can recognize each flavor component. This is how you grow your own palate, which no recipe can teach. It takes practice. 🙂 A little sriracha works miracles because it contains salt, acid, sweetness, heat, and spice. Use sparingly until achieving your perfect flavor.
Use fresh aromatics when possible. Fresh ginger and lemongrass add brightness and dimension you can’t get from other substitutes. If using ginger or lemongrass paste, you may need a little extra, as they tend to be milder. Taste as you go and adjust as needed.
Chop the potatoes uniformly. Cut the potatoes into even, 1-inch cubes so that they cook at the same rate.
Adjust the richness with coconut milk. Start with a smaller amount and add more until you reach your preferred creaminess.
Remove the chili before blending. Keeping the stem intact makes it easy to remove it at the end. This ensures gentle heat without overpowering the soup.

Serving Suggestions

Serve this Sweet Potato Soup with a swirl of coconut milk, cilantro, scallions, lime wedges, and Aleppo chili flakes.

Serve with something for dipping: Scallion Pancakes, Sourdough Rolls, Naan Bread, Sourdough, Gluten Free Bread
Serve with a side salad: Thai Quinoa Salad, Fennel Orange Salad, Kale Salad, Watercress Salad
Add a side dish: Chili Crisp Cauliflower, Coconut Creamed Spinach, Wild Rice Pilaf, Roasted Brussels Sprouts

Storage

Once cooled, store leftover sweet potato soup in an airtight container in the refrigerator for up to 4 days. Or make a large batch and freeze the soup for up to 3 months. Thaw overnight in the fridge before reheating.

FAQs

Do sweet potatoes make good soup?

Yes! Sweet potatoes get tender and caramelized, creating a silky smooth texture. Their sweetness balances well with other flavor profiles - salt, sour, spice, and heat.

How do you add flavor to sweet potato soup?

The flavor in this sweet potato soup comes from the aromatic base and the seasonings. Shallot, garlic, lemongrass, and ginger build a deeply fragrant flavor foundation, while soy sauce, lime juice, brown sugar, coconut milk, and sriracha further enrich the flavor complexity.

What flavors pair well with sweet potato?

Anything that balances well with a sweet profile, so warm spices like curry powder and turmeric and savory aromatics like garlic and shallot.

What is the most delicious way to cook sweet potatoes?

Similar to butternut squash, sweet potatoes are incredibly versatile! Here we simmer the sweet potatoes until fork-tender and purée them into a silky smooth soup. Other options are roasted sweet potatoes, baked sweet potatoes, air-fryer sweet potatoes, mashed sweet potatoes, or use them in a sweet potato casserole.

Hope you enjoy this cozy, creamy Sweet Potato Soup recipe!