
How to Thicken Soup: 8 Tips and Techniques
Soups 101
Here are eight great ways to take a soup from watery to full-bodied. Choose your method based on what you have in your pantry and what kind of soup you’re making.

1. What is a Roux? Why Should You Start With One?
If you want to ensure a thick and creamy broth base for your soup from the start (think cream of mushroom), make a roux. Roux (pronounced “roo”) is a traditional French technique for thickening sauces and soups by starting with a base of cooked flour and butter. The ratio of flour to butter varies, but it’s often 2-to-1—for most soups, ½ cup of flour and ¼ cup of butter should do it.
As for how to make a roux, start by melting the butter over medium-low heat in your soup pot. Add the flour and stir constantly with a wooden spoon until the flour has fully absorbed the butter. Continue cooking and stirring until the mixture is smooth and thick and small bubbles begin to form, about a minute. It should smell nice and nutty. At this point, you’re ready to add the ingredients for your soup. The exception: If you’re making gumbo or another soup that calls for a brown roux, keep cooking until the roux is very dark brown and fragrant—another 10 to 15 minutes.

2. Add Rice

3. Add Potatoes

4. Add Bread

5. Thicken Soup With Flour or a Starch
A “slurry” is simply a mixture of starch, such as flour, cornstarch, potato starch, or tapioca starch, whisked into water. The slurry is then added to a soup or sauce to thicken it. The reason to make a slurry rather than whisking starch directly into soup is to avoid clumping, which will most certainly happen if you sprinkle starch directly into your simmering pot. A slurry is best deployed near the end of cooking a soup, making it a good choice for when you realize that your chowder isn’t as thick as you like it or when you want your soup to have a little more body.
Make a slurry by whisking a tablespoon of starch into a quarter-cup of cold water until smooth, then add some of the broth from your soup pot and whisk to combine and help warm the slurry. Then pour it into your soup pot and stir it in. It should start thickening instantly, but be sure to let the soup come to a boil to get the full thickening power of the starch. Note: When using all-purpose flour, whisk extra well to avoid lumps, and be sure to let the soup boil for at least a full minute to thicken.

6. Add Eggs

7. Purée
