How to Thicken Tomato Soup: 10 Best Ways

Tomato soup is a tasty and timeless classic, am I right? Not only is it a great comfort food on its own, but it can also be easily upgraded. Turn up the flavor dial by adding ingredients into the soup like fresh basil, garlic or meatballs. Tomato soup also goes great with savory accompaniments like a grilled cheese sandwich. 

This comfort food can be found in a variety of forms around the world from canned tomato soup, to tomato bisque, gazpacho, or even zupa pomidorowa (Polish tomato soup).

Unfortunately, tomato soup can sometimes be way too watery. This ruins the texture and will spoil your enjoyment of your tomato soup recipe.

Never fear, though! If this is happening to you, there are steps you can take to reverse it.

Let’s check out how to thicken tomato soup. 

Why is My Tomato Soup Too Watery?

The answer to watery soup is simple, tomatoes contain a lot of water. And, if you’re like me, you probably also use the smallest bit of water to get out all the tomato goodness from the deep corner of the can. All this extra water adds up to a watery soup.

But, luckily enough, it’s easy to fix. 

How Long Does it Take to Thicken Tomato Soup?

The time it takes to thicken tomato soup can widely vary depending on the method.

Simmering it or making a cheese sauce (more on both later) can add an hour or more to the cooking time. 

However, some methods only take a couple of minutes. 

Best Methods to Thicken Tomato Soup

Let it Simmer

Of the methods to thicken your tomato soup, this one requires the least effort but a bit more time. Also, it’s great if you don’t have anything to thicken tomato soup in your cupboards. Simply leave it on the stove to simmer for a few minutes more.

Have you ever created any form of reduction, such as a pan sauce? Here, too, the process and principle are the same. More water will evaporate while the soup simmers, and it will thicken naturally.

There are a few things to keep in mind, though. First and foremost, this will have a significant impact on the final flavor. Tomatoes are high in sugar, which will continue to caramelize while the soup cooks. Cooking will also remove some of the more volatile taste components found in fresh tomatoes.

Additionally, it requires a bit of patience and a bit of stirring. If you attempt to hasten the process by turning up the heat, you’ll be rewarded with burnt soup that can be a pain to scrape off the bottom of your pot. 

For the best results, use the widest pot or pan that can hold the soup. More surface area allows the water to evaporate from the soup faster. 

Tomato Paste

If you’re a bit short on time and have an extra bit of tomato paste, then this is a great way to quickly thicken the soup. But, it can be a problem if you’ve already found the perfect taste of your soup.

Because it has such a strong tomato flavor, it can make your soup saltier or a bit sourer. So, this method works best before seasoning your soup. 

It only takes a few spoonfuls of tomato paste to get the job done. Begin with one and thoroughly stir your soup to dilute it. 

Before adding another tablespoon of paste, taste and check the consistency and add more if need be. 

If you find it to be too sour, then you can add about 1 teaspoon of sugar to balance out the acidity. 

Make a Roux

A roux is a great way to not only thicken the soup but to add an extra rich and creamy taste to the soup too. 

For it to be a true roux, it should be used as the base of the soup that helps to ensure that the soup is thick. 

However, whilst the French purists may be upset, it’s okay to add it towards the end of the cooking process if you notice that the soup will be too thin. 

  • Melt butter in a saucepan over medium heat to make the roux. Stir in equal parts flour until golden brown.
  • Then, ladle some of the soup into the roux and stir until it comes to a boil. This ensures that the flour is cooked; otherwise, your soup will have a starchy flavor. If the roux mixture is too thick, add more soup; otherwise, it’s ready when it’s thin enough to pour.
  • Pour the roux over the soup and whisk until it reaches the desired thickness.

The amount of roux you use is determined by how thick you want your soup to be. Pour 3 ounces per quart of soup for a light consistency. 

For a thicker, medium-body soup, use 4 ounces of roux per quart of soup. And for a very thick soup, use 5 ounces. 

Add Cream

Adding cream is a quick and easy way to thicken tomato soup. This method can be used in any situation but perhaps works best to thicken a homemade tomato soup recipe.

If your soup recipe already calls for cream, then you should increase the fat content in the cream since regular cooking cream is around 10% fat. In this case, you should instead use high-fat heavy cream of around 35% fat. 

For this method, wait for the soup to cool down to the eating temperature, and then add the cream. If you add it while it’s still too hot then the cream may curdle. This will ruin the soup, so be careful!

Add Eggs

Eggs will thicken your soup beautifully and you can use either whole eggs or only the yolks or egg whites too. 

In a mixing bowl, whisk two eggs until frothy. Pour a ladle of soup into the bowl and vigorously whisk until combined. Tempering is the term for this process.

Pour in the egg mixture and stir until thickened. Use only the yolks if you want a super-rich soup. Simply use the whites if you want a lighter soup.

Add Starches

Conversely to a roux, which is traditionally the base for a soup and used at the beginning of the cooking process, a slurry is quite similar but it’s added at the end and doesn’t contain fat from butter or lard, as roux does. 

You can make a slurry out of all sorts of different starches. 

I personally recommend cornstarch as it adds the best flavor compared to other starches. But, you may have your own preference too. Other options include arrowroot or tapioca starch. No matter which one you use, the ratio of starch to water is the same. 

Combine 1-2 tablespoons cornstarch or flour of choice with twice the amount of water or broth. Use a flour-to-water ratio of 1:2. Whisk it well to remove any lumps before adding it to the tomato soup and stirring for 1-2 minutes to incorporate it.

Allow your tomato soup to simmer for 5-10 minutes to incorporate the flour or cornstarch flavor, and it will thicken within a few minutes. 

Depending on the size of the pot of soup, you may need to make and add more of the slurry mixture. Experiment and make adjustments as needed but it’s best to err on the lower side and add more if you need it. 

Add Flour

Similar to starches, flour is great at thickening tomato soup too without too much work and it’s something most people will have in their pantry. You can use various types of flour like white flour, chickpea flour, or even cornflour. 

To make a flour slurry mix 2 tablespoons of flour and .25 cups of cold water and mix until it’s fully combined. Then add the mixture into the soup as you need it. 

Whilst the soup is cooking gradually add the slurry until it reaches the desired thickness. 

Add Cheese

Cheese makes pretty much anything better, right? So why not add it to the tomato soup too! 

The cheese will make the soup creamier, richer, and so much tastier in general. If you’re using a cheese that melts well, like cream cheese, you can just add it to the pot towards the end of cooking and stir it in. 

However, if you’re using a cheese that doesn’t melt well, such as parmesan cheese, first make a cheese sauce and then stir it in. 

For the best results, if you’re using a cheese sauce, you should then blend the soup with the cheese sauce to complete the dish. It’s a lot of extra work but the extra flavor will pay off. 

Add Bread

To use bread as a thickener you can try a couple of different methods. 

First, you can add a couple of slices of bread to the soup and then let it fully absorb the liquid, and then finally blend it together. Or, you can simply add croutons to the soup and allow them to absorb excess moisture. 

The croutons should be extremely dry for the best results. Store-bought croutons work very well for this. 

Add Nuts

Nuts can not only thicken the soup but since nuts are notorious for being one of the healthiest foods out there, you can get an extra nutrient boost too. 

To use nuts as a thickener you should first make nut flour and add 1-2 tablespoons of nut flour for every quart of tomato soup. 

This works the best if you add the nut flour at the beginning of the cooking process as it takes longer than bread or normal flour to absorb the excess liquid.