- You can thicken soup with flour or cornstarch, which do not add any additional flavor.
- If you want more flavor, a roux is the best way to thicken up a soup.
- Starchy add-ins are another great way to create thick and creamy vegan soups.
Making soup is a bit of an art, and the right texture and consistency could be the difference between a good bowl and a delicious one.
Consistency can make a big impact on flavor, says chef Matt Broussard, who uses his online platform to teach folks how to cook well. "Mouth-feel is a really important part of the eating experience," he says.
But, we've all been there. Maybe you've accidentally added too much liquid, or maybe you're looking at the website's photographs and your soup just doesn't have the same texture.
Troubleshooting in the kitchen is part of the natural process, and soup is a very forgiving dish to thicken and doctor up to your liking. Here are five easy ways to fix it.
Method 1: Whisk in a slurry of cornstarch or flour
Flour and cornstarch are both pantry staples, and they work great as thickening agents thanks to their water absorption abilities, which increase when heated. Not only is it as simple as making a quick slurry, this method also won't impact the flavor of the soup.
To thicken soup using flour or cornstarch, measure out the flour or cornstarch in a separate bowl — start with 1 tablespoon per cup of soup. Add equal parts water or soup liquid to the flour or cornstarch and whisk until they're completely combined in a slurry. Once you've created the slurry, slowly whisk it into soup liquid and bring it back to a simmer.
Keep in mind you can always make and add more slurry if the consistency is still too thin for your liking. This is a versatile method to thicken most soups and stews. For example, Broussard reaches for a cornstarch slurry to thicken Hot and Sour soup.
Quick tip: Broussard recommends a vegetarian gelatin substitute made from seaweed called agar-agar as a substitute for cornstarch. You only need half the amount of agar-agar than you would need cornstarch, so use a 2 to 1 ratio when substituting.
Method 2: Make a roux
Broussard's favorite way to thicken soup is by adding a roux, which is a mixture of equal parts flour and fat (typically butter) that's cooked slowly over low to medium heat.
Roux is typically the first step in making gumbo. But as a thickening agent, it can be added at any stage. A roux imparts a nutty, buttery flavor that you can't get with cornstarch or other thickening methods. It is an excellent option for making rich, creamy soups like lobster bisque, or clam chowder.
There are four main stages of roux:
- White roux is cooked for about 5 minutes just to remove the raw flour taste.
- Blonde roux is achieved after
cooking the roux for about 10 to 15 additional minutes, giving it a golden hue. - Brown and dark brown roux are cooked for roughly 30 to 45 minutes. The color deepens overtime and this helps develop a rich, nuttier flavor while cooking flour out. Because of this, the darker the roux, the less it will thicken up your soup.
To make a roux, you'll need about 3 ounces of roux for each quart of soup liquid you want to thicken. To do this, use 1.5 ounces of butter, or roughly 3 tablespoons, and 1.5 ounces of flour, or roughly 5 and a half tablespoons. You can use more per quart if you want to create an even thicker consistency.
In a skillet, melt the butter over medium-low heat, then sprinkle the flour in. Stir the butter and flour constantly until the mixture turns light golden brown. The process typically takes 3 to 5 minutes.
Method 3: Add dairy
Dairy works well if it has a high-fat content, says Broussard. The best options for thickening soup are cream or half and half. Plain yogurt or even freshly grated cheese works well and adds an extra layer of tangy, salty flavor. Add the dairy at the end and avoid bringing the soup to a boil since this can cause yogurt, cheese, or cream to split.
When adding dairy to soups, start with a small amount. Stir to see if the consistency is right and add more if needed.
Dairy works well in any kind of soup but is best if you're looking for a creamy texture.
Quick tip: Some store-bought non-dairy alternatives don't have the same fat content needed to add creaminess to the soup like dairy, but a homemade cream using nuts does the trick. Blend 1/2 cup of raw, neutral-tasting nuts or seeds (soaked in water for a few hours) with 1 cup of water to make a cream replacement.
Method 4: Blend up part of the soup
Blending a portion of the soup creates an emulsion, especially if it has starch in it like potatoes or beans. The easiest way to blend soup is using an immersion blender.
Alternatively, you can also scoop out some soup and blend it in a regular blender then add it back in. This is a quick hack, especially if you're vegan, because it adds creaminess without needing special substitutes or ingredients.
"[Blending] works better if you want a pureed soup instead of something with more texture," says Broussard.
You can choose to blend the entire pot of soup or blend it partially for a chunkier consistency. A good rule of thumb is to blend about a third of the soup, which creates some creaminess while retaining texture.
Best blenders
We test and recommend the best blenders and immersion blenders. Check out our picks:
- Best blender overall: Vitamix 5200, $385.18 on Amazon
- Best mid-priced blender: Cleanblend 3HP Commercial, $178.97 on Amazon
- Best immersion blender overall: Breville Control Grip Immersion Blender, $99.95 on Williams Sonoma
- Best immersion blender on a budget: Braun MultiQuick Immersion Hand Blender, $64.95 on Amazon
Method 5: Incorporate starchy add-ins
Adding starchy foods like rice, potatoes, pasta, and beans can also help thicken up a soup while adding texture and body. As they cook, they release starches, creating a thicker consistency.
Beans and potatoes are an especially great choice for making creamy, dairy-free vegetarian or vegan soups.
Broussard recommends adding starches at the start of the cooking process, aside from pasta, which you should add according to the package's cook-time, so they have enough time to break down and alter the soup's texture.
Insider's takeaway
You can use a cornstarch slurry, a roux, dairy, or starchy add-ins to thicken a soup. Blending a veggie-laden soup will also help thicken it up.
The method you choose depends on your desired consistency and your dietary requirements. Want a creamy texture but prefer to avoid dairy? Use beans or potatoes. Need to thicken up a soup without altering its flavor? Use a cornstarch slurry.