How To Thicken Tomato Soup
If you love cooking and spend a generous amount of time in the kitchen, chances are you will have experimented with some ways to improve your dish or rectify any flops. I love being in the kitchen, and I have had my fair share of flops, so I have a few tips on how you can easily thicken your tomato soup for a warm hearty soup that hits the spot.

Thickening tomato soup can be done in various ways using starch flour, starchy vegetables, adding cream, eggs, and cheese. Using the right tomatoes can also make a difference to the thickness of your soup, and roasting them before jumping directly into making the soup can help reduce excess water.
Tips On How To Thicken Tomato Soup
Don’t feel alone if you planned to make a delicious pot of heart tomato soup and it turned out a watery mix, but here are some tips that I learned to get that soup back on track and serve up a masterpiece.

Tip #1: Allow Your Soup To Simmer
The simplest and cheapest way to thicken your soup is to give it a little extra cooking time. Allow the soup to simmer uncovered over low to medium heat, which will allow the extra juice to evaporate and thicken naturally. This is also the ideal way to retain the original delicious flavors of the soup without changing any of the delicate flavors and textures.
Use this method also for thickening marinara sauce or cooked salsa.
Tip #2: Blend Your Tomato Soup
Another easy way to thicken your soup without changing flavor profiles is to blend it. You can a portion at a time in a high-powered blender or food processor, adding it gradually to the remaining soup in the pot until you have the consistency you want.
Or you can blend the whole pot at once with an immersion blender to puree the soup, giving you a smooth thick delicious soup.
Tip #3: Add Tomato Paste
Adding tomato paste is a sure way to thicken up a watery tomato soup, and since it’s made from tomatoes, it makes sense to add some to the soup.
However, utilize the tomato paste sparingly when using this method, as the concentrated paste can change the flavor of your soup. It may make it saltier and is best used before spicing up your pot. Start off diluting one spoon at a time until you reach the consistency you want.
Tip #4: Incorporate Starchy Vegetables
Adding some starchy vegetables can add extra texture and flavors to your soup, but it can also help thicken it (this method can also be used for thickening gumbo or baked beans!)
Adding some cubed starchy vegetables will help absorb some liquid while it is cooking, and vegetables like potatoes and butternut squash release starch when they cook, which will thicken up the soup simultaneously.
Here are some ideas for starchy vegetables that you can add to your soup to help thicken it up.
- Sweet potato
- Butternut squash
- Red lentils
- Potatoes
- Beans
Red lentils are also a great combination with tomato soup and will quickly add body to the soup. Throw some red lentils into the soup, which will absorb liquid while it cooks and swells; once they are soft, mush them into the soup to thicken up the pot.
Tip #5: Add Instant Potato Flakes
Using some instant potato flakes or instant mash is another great way to thicken up your soup, but be careful and use a little at a time until you reach the consistency you want; adding too much may end up with a red mash instead of a creamy tomato soup.
Tip #6: Add Cream Or Greek Yoghurt
Adding heavy cream or Greek yogurt in the last twenty minutes of your soup cooking process not only helps to thicken it but also gives the soup a rich and creamy texture, with the Greek yogurt adding a new tangy dimension to your soup that works really well with tomato soups.
Remember to allow the soup to simmer gently in its pot once you have added the cream or yogurt, as boiling it may cause it to separate.
Tip #7: Make A Slurry Using Starch Flour
You can make a slurry to thicken your soup using any of the below starch flours.
- Cornstarch
- Arrowroot
- Tapioca
- Potato starch
A slurry is a mixture of any of the above starches with a little cold water that you add at the end of the process by mixing it in a separate bowl until smooth, then adding a little at a time to the soup.
Bring the pot to a boil and watch the soup thicken immediately, but remember to stir as you pour in the mix constantly, or you may have a lumpy soup; and do not use it in excess, or it may change the flavors of your delicious soup.
Tip #8: Make A Roux Using Flour
A Roux uses a similar process to a slurry, but in this process, an equal part of any flour and butter is used to make a thickening agent. This mix adds a creamy texture to your soup without using any creams. Below are some ideas of flours that you can use.
- Wheat flour
- Chickpea flour
- Oat flour
- Quinoa flour
- Rice flour
Use unsalted butter that is melted in a pan and add equal parts of flour, mixing it to form a smooth paste. Add some broth to the mix, stirring until you get a smooth paste, and then add to your soup, constantly stirring until it thickens.
Tip #9: Add Eggs
Not exactly the first item that comes to mind when wanting to thicken a soup, but the addition of eggs is a great way to add rich flavors to your soup. You can use the whole egg, or only the egg yolk for a richer and deeper flavor, or just the egg whites for a lighter soup.
Whichever way you decide to go, remember to temper the egg before adding it to the soup, or you may land up with a scrambled tomato soup.
Tempering the egg is when you crack your egg in a separate bowl and gently ladle in some of your soup while vigorously whisking the concoction until you have a smooth mix. Once the right consistency is achieved, pour into the soup and stir until it thickens.
Tip #10: Add Some Cheese
No matter what your favorite flavor of cheeses is, you can add some sprinkles of cheese to thicken up a tomato soup, but it also adds a different taste to the soup, elevating its texture and flavors to be richer and creamier.
Tip #11: Add Nuts To Thicken The Soup
Adding nuts is another way to thicken your tomato soup, and it’s vegan too. But because nuts can have a very distinctive taste, it is always better to stick to neutral flavors such as,
- Almond nuts
- Cashew nuts
Making a smooth cream from either of these nuts will instantly thicken your soup and add a new nuttier dimension to the flavors. Add your nuts with a bit of water or broth in a blender or high-powered mixer and mix until you are left with a creamy smooth paste. Pour the creamy liquid into the pot and allow to simmer on low until your soup thickens.
Tip #12: Add Croutons
Another creative way to thicken your watery soup is by layering some croutons or bread on top of the soup. The bread will soften and absorb the liquid; the bread will finally become soft and melt away into the soup, thickening it up simultaneously.
A fun way to add dimension and flavor to the soup is to add flavored croutons to insert a little extra “je ne sais quoi” flavor profile to the soup.
More Questions Thickening Tomato Soup
Now that you are loaded with tips and ideas on how to thicken your delicious tomato soup, there is one thing left to do, and that’s cook up a storm, but before you go, here are some more helpful frequently asked questions to help you decide on a thickening agent.
What Is A Healthier Way To Thicken Tomato Soup?
There are healthier alternatives to thickening tomato soup than traditional cornstarch or flour. Using eggs and nuts is a more natural way to use low-carb products to thicken your soup. Instead of butter and oils, you could use avocados which are also another great healthy alternative to give body to your soup.
Which Is Better To Thicken Tomato Soup; Flour Or Cornstarch?
In my personal experience, I found that cornstarch or corn flour works better when thickening my soups. However, with that said, it greatly depends on how much thickening you need to do.
If you need to use a lot of flour to thicken up a watery soup, then it is best to go with the normal flour, as too much cornstarch can change the flavor profile of your soup and leave it with an undesired starchy taste.
How Can I Thicken My Tomato Soup Without Using Carbs?
Sometimes we don’t want to add extra carbs when thickening soups and just looking for something a little healthier with fewer calories. So thickening your tomato soup with some keto-thickening agents is also possible. Below are a few that can be handy to have around.
- Xanthum gum
- Glucomannan
How to Prevent Watery Tomato Soup
If it’s tomato season and you need to use up your stock, making a fresh batch of tomato soup is the ideal opportunity.
Using dense, oblong tomatoes from the plum variety with little juice will ensure you don’t boil up a pot of watery tomato soup. Below are some of the most popular tomatoes you can use for your delicious soup.
- Roma
- San Marzano
- Amish paste
- Big mama
- Supremo
- Ropreco Paste
Taking the time to roast the tomatoes slowly is a great way to ensure your soup is a success, and this method adds a great depth of flavor to your soup. You can use this alone or in conjunction with tin tomatoes to reduce your soup’s water content and accentuate the flavors.
Adding some sundried tomatoes is also a great way to use less watery tinned tomatoes and reduce the water content, but it also adds that extra burst of concentrated flavors.
Although you are not always guaranteed to find the perfect tomatoes in season, if you can’t find fresh tomatoes, don’t sweat; you can always use canned tomatoes, but to ensure you don’t land up with a watery mess, try to find canned San Marzano.
When using canned tomatoes, try to drain the liquid from the can and don’t rinse the can out. But if you are still left with a diluted soup, we also have some great tips for easily thickening your soup for that perfect bowl of delicious tomato soup.
Conclusion
Tomato soup is a hearty, healthy meal to have on a cold winter day. It is easy enough to make at home, but sometimes you might find the soup in need of thickening if something goes wrong. To thicken tomato soup, you can use a variety of ingredients like tomato paste, cheese, cream, or other vegetables. Which method is your favorite?