How to Thicken Soup, According to Our Test Kitchen

There's nothing more inviting than a big pot of soup simmering on the stove. From seafood chowders to creamy bisques, soup makes the perfect appetizer or main course. But sometimes a recipe doesn't go quite as planned, and you're left with a soup that's not the right consistency. Here, learn how to thicken up soup by using additions like cornstarch, beans and other easy solutions.

Pictured recipe: Cream of Zucchini Soup

How to Thicken Soup with Cornstarch

Cornstarch is a great option as it is a natural thickening agent, but you'll want to be careful about how much you use. Start with 1 tablespoon of cornstarch whisked together with cold water to create a slurry. Then, gradually add the slurry to the soup, letting it boil for one to two minutes before adding more. This method allows you to adjust accordingly as the soup is being thickened (you might not need the entire slurry or you might need more, depending on the viscosity of the soup and the texture you're aiming for). You can also substitute potato starch or rice starch for the cornstarch.

How to Thicken Soup with Flour

Pictured recipe: Creamy Corn Soup with Crispy Bacon

If you don't have cornstarch handy, flour is a similar alternative that can be used to thicken soup (for a gluten-free option, you can also use arrowroot flour). There are a few ways to incorporate flour into soup, which work to avoid clumping and the raw taste of flour. First, you can create a slurry by whisking 2 tablespoons of flour with cold water and adding it gradually to the soup.

Another method of using flour to thicken soup is by making a roux on the stovetop. A roux, which is a mixture of fat and flour, is often used as a base for sauces and is an easy way to add starch. If you're looking for an alternative, you can also make a beurre manié, which is a mixture of flour and butter rubbed together to create a dough or paste. With both methods, you'll want to add them to the soup bit by bit to gauge the soup's thickness.

How to Thicken Soup with Dairy

Another option for thickening soup is by using dairy like sour cream or yogurt. Start with a small dollop and stir before checking the consistency and adding more. We recommend using plain yogurt so you don't alter the taste of the soup. You can also use cream if you prefer.

How to Thicken Soup with Rice, Bread, Potatoes or Beans

Foods like rice, bread, potatoes and beans are naturally high in starches, which, when broken down, act as a thickening agent. With rice, the grains will break down into the soup as it's simmered and stirred, releasing the starches and thickening the soup.

Aside from rice, you can also use bread, potatoes or beans, according to Breana Lai Killeen, M.P.H., RD. Killeen says, "When stirred into soup, stale bread, mashed beans and mashed potatoes cook down to create a creamy, rich texture, all without adding cream. It's also a great way to use up leftovers." If you don't have these ingredients on hand, you could also try using tortillas as a thickener, like in this Chicken Enchilada Soup.

How to Thicken Soup by Blending It

One easy way to thicken soup is by blending it—or part of it, at least. If your soup is packed with vegetables, you can blend part of it to change the texture. The blended vegetables will help thicken the consistency of the soup. To do this, take half of the soup, add it to a blender and blend until smooth (use caution when blending hot liquids; you can also use an immersion blender). Return the blended portion to the soup and stir before eating.