Easy Keto Marinara Sauce is perfect with your favorite low-carb pasta, on pizza, or in a casserole. You won’t go back to store-bought after trying this! Simmered to excellence, this low carb tomato sauce is a great way to add flavor. This easy Sugar Free Spaghetti Sauce Recipe preps in less than 5 minutes.
We love all sorts of Italian dishes at our house, and having a really great quality sugar free spaghetti sauce recipe is a must. The entire family loves the flavor, and they don’t even care or realize it’s low-carb. They will eat it without complaint, and that leaves me pretty happy too.
I also love how versatile this low carb keto marinara sauce is. You can use it for so many different recipes, and it tastes delicious. Dipping these Keto Breadsticks into the sauce is one of our favorite sides for dinner.
Canned San Marzano Tomatoes - Canned San Marzano tomatoes are a popular choice among chefs and home cooks alike for their exceptional flavor and quality. These tomatoes are grown in the fertile soil of the San Marzano region in Italy, known for producing some of the best tomatoes in the world. The canning process ensures that the tomatoes retain their rich, sweet taste, vibrant red color, and firm texture. Whether used as a base for pasta sauces, soups, or stews, canned San Marzano tomatoes add an unmistakable depth of flavor to any dish. Their versatility and unmatched taste make them a pantry staple for those seeking to elevate their culinary creations.
Salted Butter - Adding salted butter to spaghetti sauce can enhance the overall flavor and richness of the dish. The creamy texture of the butter helps to balance out any acidity in the sauce, creating a more well-rounded taste. Additionally, the saltiness of the butter adds depth and complexity to the flavors, making each bite more satisfying. Whether it's a tomato-based or cream-based sauce, incorporating salted butter can take your spaghetti sauce to a whole new level of deliciousness.
Onion - To enhance the flavor and add a subtle sweetness to my spaghetti sauce, I always include a whole halved onion. As the sauce simmers, the onion releases its aromatic essence, infusing the dish with depth and complexity. The natural sugars in the onion caramelize, creating a rich and savory undertone that perfectly complements the tanginess of the tomatoes. Whether I'm making a traditional marinara or a hearty meat sauce, this simple addition of a halved onion elevates my spaghetti to new levels of deliciousness.
Salt & Pepper - Adding salt and pepper to spaghetti sauce enhances the flavor profile of the dish. The salty notes from the salt help to balance out the acidity of the tomatoes, while also bringing out the natural sweetness of the ingredients. Meanwhile, the black pepper adds a subtle spiciness that complements the richness of the sauce. Together, these seasonings elevate the overall taste of the spaghetti sauce, creating a harmonious blend of flavors that make each bite more enjoyable.
Sweetener - Adding a sweetener to spaghetti sauce can be a game-changer for those who prefer a balance of flavors in their pasta dishes. The addition of a sweetener helps to cut through the acidity of the tomatoes and brings out the natural sweetness in the sauce. This subtle touch enhances the overall taste profile but you can omit it if preferred.
How To Make Keto Marinara Sauce
This is one of the most simple low carb marinara sauce recipes ever. Mostly you add in the ingredients stir it every once in a while, and it does the work for you. Let’s take a look:
First Step: Add the tomatoes, onions, butter, salt, and pepper in a pot over low-medium heat. Stir to prevent sticking and let it simmer for one hour.
Second Step: After the hour is up, you can take the onions out of the pan. Either add them to another recipe or discard. Add any extra salt and pepper that you want as well as any sweetener that you like. You can add also add fresh basil to the keto spaghetti sauce recipe to taste as well.
This is an easy recipe to customize to fit your taste buds. Here are a few ideas you might like to try out to customize this sugar free spaghetti sauce recipe:
Garlic - Add 1-2 cloves of minced garlic to the sauce if you love garlic. Adding in roasted garlic is even better!
Oregano - If you love oregano, you can add fresh or dried to the marinara sauce. Just add as much as you like to flavor it.
Red Pepper Flakes - If you like a little bit of spice in your sauce, feel free to add a dash or two of crushed red pepper flakes. Don’t go overboard and make it too spicy, but just add a little bit.
Italian Seasoning - You could add a teaspoon or so of your favorite Italian seasoning to enhance the flavors too.
Why do you put Butter in Marinara Sauce?
Yes! Using butter instead of extra virgin olive oil gives the sauce a slightly creamy note that is delicious. You may not believe it but I got the idea for this sauce from a Nicholas Sparks novel. One of the characters makes a similar sauce and ever since I read that book 10 years ago I've made this version of it.
Why Should I Make My Own Sauce?
There are several reasons to make your own keto pasta sauce recipe at home. First of all, you will know every ingredient that goes into the sauce. There are no surprises, and you already know that it’s going to be good for you. Store-bought sauces can be filled with added sugar, preservatives, and ingredients that just aren’t good for you, especially on a keto diet, with lots of net carbs.
Secondly, it’s a frugal way to save some money. You can very inexpensively make gluten free homemade marinara sauce and have so much more than what comes in a jar from the market. I get the appeal of buying it pre-made, but honestly, this comes together so FAST, and it’s mostly hands-off.
Does The Marinara Sauce Need Sweetener?
This is completely up to you whether or not you want to add sweetener to the low carb pasta sauce recipe. I recommend preparing the sauce and tasting it before deciding. Tomatoes are typically fairly sweet, so adding sweetener may make it too sweet for your tastes. Whatever you like is going to be the right answer to create your own favorite pasta sauce recipes.
How Long Does Homemade Marinara Last?
The low carb spaghetti sauce will last around 4-5 days if kept in the fridge. Let it cool down before putting it in the fridge. You should keep it in an airtight container or jar with a lid.
Another idea would be to make an extra-large batch or two and let it cool. Once cooled, pour the sauce into some freezer-safe ziplock bags. Don’t fill them to the top, just about ⅔ full to make room for the sauce to expand. Remove any excess air, lay flat, and put in the freezer. The low carb marinara sauce will last 3-4 months in the freezer. You can warm it up in a saucepan or in the microwave when ready to eat it.
Ways to Use a Tomato Sauce Recipe
There are many ways to use low carb marinara sauce in your favorite keto recipes besides just pouring it over your favorite keto pasta noodles sub or using as pizza sauce. Serve homemade spaghetti sauce on spaghetti squash with some Instant Pot Turkey Meatballs or Italian sausage for a quick meal.
I use this in my Keto Pizza Casserole, on Low Carb Chicken Parm, and even as a base for tomato soup. You can use it in any recipe that calls for pasta sauce. For a vegetarian choice try it in my Eggplant Gratin or Cauliflower Parmesan. There is something about Italian food that equals comfort food to me.
- 56 oz whole San Marzano tomatoes (2 large cans)
- 1 onion peeled and halved with the root end intact
- 4 oz butter
- salt & pepper to taste
- fresh basil optional, chopped
- sweetener optional, to taste
- Combine the tomatoes, onion, and butter in a large stockpot. Simmer one hour.
- Discard the onion (or save for another use). Add salt and pepper to taste. Add sweetener and basil, if desired.
Originally Published August 10, 2020. Revised and Republished July 18, 2023.