How To Thicken Spaghetti Sauce or Pasta Sauce

A well-prepared pasta sauce can make all the difference in a delicious spaghetti dish. Oftentimes, achieving the perfect consistency is a challenge for many cooks. It’s important to understand some of the techniques that can be employed to thicken spaghetti sauce, so that it clings to the pasta just right, resulting in a delectable, satisfying meal.

There are various methods to thicken pasta sauce, ranging from simple pantry staples to low-and-slow cooking techniques. It is essential to remember that each approach will have different effects on the ingredients and the overall taste of the dish. This ensures that the thickening method chosen will complement the desired flavor profile of the sauce, and cater to different dietary preferences.

In this article, we will explore some of the easiest and most effective ways to thicken a spaghetti or pasta sauce. These methods cater to a variety of tastes, textures, and dietary preferences, making it easy for anyone to master this essential cooking skill.

Spaghetti sauce

Fundamental Thickening Techniques

Reducing by Simmering

One way to thicken spaghetti sauce or pasta sauce is by reducing it through simmering. This method involves heating the sauce over a low heat and allowing it to cook down until the excess liquid evaporates. To achieve this:

  1. Pour the sauce into a large saucepan and heat it over medium-low heat.
  2. Let the sauce simmer uncovered, stirring occasionally to prevent sticking or scorching.
  3. Continue to cook the sauce for about 20 to 30 minutes or until it reaches the desired consistency. Remember that the sauce will thicken as it cools.

Keep in mind that reducing the sauce will also concentrate the flavors, so it’s a good idea to taste the sauce periodically and adjust the seasonings if necessary.

Using Starches

Another effective way to thicken spaghetti sauce or pasta sauce is by incorporating starches. Some common starches used for this purpose include cornstarch, flour, and tomato paste. Here’s how to use each:


  1. Mix 1 tablespoon of cornstarch with 2 tablespoons of cold water to create a slurry.
  2. Stir the slurry into the hot sauce and continue to cook for a few minutes, stirring constantly until the sauce thickens.


  1. Make a roux by mixing equal parts all-purpose flour and a cooking fat (such as butter or oil) in a separate saucepan over low heat. Cook, stirring constantly, until the mixture turns a light golden color.
  2. Gradually add the hot sauce to the roux, whisking well to combine. Continue cooking and whisking until the sauce reaches the desired thickness.

Tomato paste:

  1. Add 1 to 2 tablespoons of tomato paste directly to the sauce, stirring it in until well combined.
  2. Cook the sauce, stirring constantly, for a few minutes to allow the flavors to meld and the texture to become smoother.

These starch-based methods can provide a quick fix for thin pasta or spaghetti sauce. Experiment with the various starches to achieve the perfect consistency and flavor for your sauce.

9 Easy Ways To Thicken Spaghetti Sauce

Common Thickening Agents

Using a Roux

A roux is a classic thickening agent made from a combination of flour and fat, typically butter. To create a roux, melt butter in a pan over low heat and gradually add an equal amount of flour. Stir the mixture continuously until smooth and cook it to your desired color. This process can add a rich, velvety texture to your spaghetti sauce while also thickening it. Make sure to add the roux gradually to your pasta sauce and continue stirring to prevent lumps.

Cornstarch Slurry

A cornstarch slurry is a mixture of cornstarch and cold water. It serves as a quick and easy thickening agent. Add one part cornstarch to two parts cold water then stir to form a smooth paste. Gradually pour the slurry into your simmering sauce, stirring continuously. The sauce will thicken as it heats, so monitor the process closely to achieve the desired consistency. Take note that cornstarch increases the sauce’s glossiness and provides a translucent finish. However, it generally doesn’t affect the flavor or taste of your homemade pasta sauce.

Adding Mashed Potatoes

Mashed potatoes are not only a great side dish but also a useful thickening agent for pasta sauce. They enrich the sauce without altering its flavor. To utilize mashed potatoes as a thickening agent, add a few spoonfuls to your sauce while it is simmering. Stir the sauce until the mashed potatoes are evenly incorporated. Adjust the amount of mashed potatoes based on your desired consistency.

Incorporating Vegetables

Vegetables can be an excellent way to thicken and enhance the flavor of your spaghetti sauce. Options like tomatoes, carrots, zucchini, and bell peppers are particularly effective for this purpose. Simply chop or puree the vegetables and add them to your sauce. Let the sauce simmer until the vegetables soften and naturally thicken the sauce. The addition of vegetables not only thickens your sauce but also adds nutritional value and a more complex taste.

Advanced Thickening Techniques

Adding Egg Yolks

One way to thicken spaghetti sauce is by adding egg yolks. Start by beating 1-2 egg yolks in a separate bowl. Gradually add a few tablespoons of the hot sauce into the bowl with the egg yolks, whisking constantly to temper the yolks. This step is essential to prevent the yolks from curdling. Once the egg yolks are tempered, slowly pour the mixture back into the pot of sauce, stirring continuously. The addition of egg yolks will give the sauce a rich, velvety texture.

Important note: After adding the egg yolks, avoid boiling the sauce to prevent curdling. Keep the heat at a gentle simmer.

Incorporating Cheese

Cheese is another excellent thickener for spaghetti or pasta sauce. Start by grating a suitable cheese, such as Parmesan, Romano, or even cheddar. To incorporate the cheese into the sauce, first remove the pot from the heat source. Then, gradually add the grated cheese to the sauce, stirring until it melts and combines. The amount of cheese needed will depend on the desired thickness; start with about 1/4 cup and adjust as necessary. Besides thickening, this method also adds a depth of flavor to the sauce.

Using Ground Meat

Adding ground meat to spaghetti sauce can also help thicken it. To avoid making the sauce too watery, drain any excess liquid from the meat before adding it to the sauce. In a separate pan, heat 1 tablespoon of olive oil and cook the ground meat until browned. Drain the fat and add the cooked meat to the sauce. The incorporation of ground meat not only adds thickness but also protein and flavor.

Helpful tip: If using canned tomatoes, consider draining some of the liquid to reduce the overall watery consistency of the sauce.

Texture and Flavor Enhancers

When trying to thicken spaghetti sauce or pasta sauce, there are several ways to enhance both the texture and flavor of the dish. These methods range from incorporating breadcrumbs and grated parmesan to caramelizing vegetables and adding chunky ingredients.

Using Breadcrumbs and Grated Parmesan

One simple way to thicken your sauce is by using breadcrumbs and grated parmesan cheese. These ingredients can help absorb excess liquid and create a thicker consistency for your marinara or bolognese sauce. To do this, simply add a small amount of breadcrumbs or grated parmesan to your sauce as it is boiling and continuously stir until you achieve the desired thickness. Be careful not to add too much, as this can adversely affect the flavor and texture of the sauce.

Caramelizing Vegetables

Caramelizing vegetables is another method to enhance the texture and flavor of your sauce. By cooking vegetables like onions, carrots, and bell peppers over medium heat until they become soft and slightly browned, you can add depth and richness to your sauce. Once caramelized, add the vegetables to your boiling sauce and let them simmer together for a few minutes to incorporate their flavors. This method works particularly well for bolognese sauce or lasagna, as the caramelized vegetables complement the traditional ingredients used in these dishes.

Adding Chunky Ingredients

For a thicker, chunkier sauce, consider adding ingredients like Italian sausage, mushrooms, or additional vegetables. These items can provide more substance to your sauce, enhancing both its texture and overall presentation. To incorporate these ingredients, simply cook the meat or vegetables separately, then add them to your sauce as it is boiling.

Some options for chunky ingredients can include:

  • Italian sausage: Cooked and crumbled or sliced, this ingredient adds a hearty flavor and texture to spaghetti sauce.
  • Mushrooms: Sliced and sautéed, mushrooms provide an earthy taste and a substantial texture to pasta sauces.
  • Vegetables: Chopped and cooked, vegetables such as zucchini, bell peppers, or eggplant can contribute extra substance to your sauce.

Remember that thickening your sauce can also be achieved by using a cornstarch slurry. This method involves mixing a small amount of cornstarch with water and slowly adding it to the boiling sauce. Stir continuously until the desired thickness is reached.

Troubleshooting and Adjustments

Fixing Over-Thickened Sauce

If you find your homemade spaghetti sauce has become too thick, there are a few ways to adjust it. One option is to simply add water or chicken broth to thin it out. Start by adding a small amount, and gradually add more until you reach your desired consistency.

Another option is to add a roux, which is a mixture of flour and butter often used in French cooking to thicken sauces. However, this method might not be ideal for those looking to limit calories, as adding a roux will increase the caloric content of the sauce.

Instead, try adding egg yolks for a thickening ingredient with a more neutral flavor. Whisk the egg yolks into the sauce gradually, making sure to temper them by adding some hot sauce to the yolks before mixing them in. This will prevent the yolks from cooking too quickly and creating lumps.

Balancing Flavor

When adjusting the flavor of your spaghetti sauce, be mindful of the following:

  • Adding meat: You can enhance the flavor of your sauce by adding ground beef or sausage. This will not only add a different dimension of flavor but also increase the sauce’s thickness. Cook the meat separately before adding it to the sauce to ensure that it is cooked through.
  • Too salty: If your spaghetti sauce is too salty, try adding a small amount of sugar or a splash of vinegar to help balance the flavors. Be careful not to add too much sugar, as it can overpower the natural sweetness of the tomatoes.
  • Al dente pasta: To ensure that your pasta is cooked to the perfect al dente texture, cook the pasta separately and add it to the sauce just before serving. This will prevent the pasta from becoming too soft and mushy from overcooking in the sauce.

By following these troubleshooting tips and adjustments, you’ll be able to create a delicious spaghetti sauce that’s perfectly thickened and flavored to your satisfaction.

Alternative Methods and Recipes

Using Shredded Carrots and Eggplant

One approach to thicken pasta sauce is by incorporating shredded carrots or eggplant. Adding these vegetables to the sauce not only thickens it, but also introduces an additional layer of flavor. Begin by sautéing shredded carrots or diced eggplant in a pan until they are soft. Then, add them to your pasta sauce and let it simmer for about 15-20 minutes, allowing the vegetables to absorb some of the sauce and thicken it in the process.

Creamy Texture Techniques

To achieve a creamy texture in your pasta sauce, you can utilize proteins such as heavy cream, cream cheese, or even mascarpone cheese. These dairy products are great options for increasing the thickness of your sauce while also imparting a rich, velvety taste. Simply stir in your desired protein until it is fully incorporated into the sauce. Keep in mind that adding too much cream-based product can result in a heavy sauce, so exercise moderation to preserve the balance of flavors.

  • Heavy cream: 1/4 cup per cup of sauce
  • Cream cheese: 2 tablespoons per cup of sauce
  • Mascarpone cheese: 2 tablespoons per cup of sauce

Utilizing Starchy Pasta Water

A simple yet effective technique to thicken pasta sauce is by incorporating starchy pasta water. Before draining your cooked pasta, reserve about 1/4 to 1/2 cup of the cooking water. The starchy water will act as a thickening agent when added to your sauce, helping to create a thicker, more cohesive dish. Start by adding a small amount of the reserved water to the sauce, stirring it in until your desired consistency is reached. This method also allows the sauce to better adhere to the pasta, enhancing the overall dish.

Spaghetti sauce

How To Thicken Spaghetti Sauce

Quick and easy way to thicken spaghetti sauce.
5 from 1 vote
Prep Time 10 minutes
Cook Time 1 hour
Total Time 1 hour 10 minutes
Course Main Course
Cuisine American, Italian
Servings 4
Calories 200 kcal


  • Large saucepan
  • Whisk


  • 1/4 cup olive oil
  • 1/4 cup all-purpose flour
  • 1 onion diced
  • 2 cloves garlic minced
  • 1/4 teaspoon red pepper flakes
  • 1 teaspoon dried basil
  • 1 teaspoon dried oregano
  • 1 teaspoon dried parsley
  • 1 teaspoon salt
  • 1/2 teaspoon black pepper
  • 1 can 28 ounces crushed tomatoes
  • 1/2 cup water


  • Heat olive oil in a large saucepan over medium heat.
  • Add the flour and whisk until combined. Cook for 1-2 minutes, stirring constantly.
  • Add the onion and garlic and cook until softened, about 5 minutes.
  • Add the red pepper flakes, basil, oregano, parsley, salt, and black pepper and stir to combine.
  • Add the crushed tomatoes and water and bring to a simmer.
  • Reduce heat to low and simmer for 60 minutes, stirring occasionally.
  • Serve over spaghetti or your favorite pasta.


Calories: 200kcalCarbohydrates: 20gProtein: 4gFat: 12g
Keyword How to Thicken Spaghetti Sauce
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Cassie brings decades of experience to the Kitchen Community. She is a noted chef and avid gardener. Her new book "Healthy Eating Through the Garden" will be released shortly. When not writing or speaking about food and gardens Cassie can be found puttering around farmer's markets and greenhouses looking for the next great idea.
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