Keto Spaghetti Sauce
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Make my keto spaghetti sauce recipe whenever you need a rich, deeply flavorful red sauce. It’s easy to make, completely sugar-free, and perfect over low-carb pasta! 3 grams of net carbs.
I’ve been making spaghetti sauce from scratch for years, ever since my mom shared her recipe with me. Since going keto, I’ve had to give my favorite recipes a low-carb makeover.
I didn’t have to stray far from her original recipe; I just swapped sugar for something else. I tested a few options (monk fruit and allulose), and allulose dissolved the best and tasted closest to sugar.
Made with tomatoes, fresh garlic, and onions, it doesn’t taste keto- it just tastes homemade.
Table of Contents
Arman’s recipe highlights
- Homemade always tastes better. I control the salt, and there are no preservatives. Use it with my keto spaghetti!
- Versatile. It’s perfect over pasta, over vegetables, and even thick enough for pizza sauce.
- Freezer-friendly. If I’m making spaghetti sauce, you better believe I’m making extra to freeze for later. It lasts up to 6 months.
Key Ingredients
Here’s what you’ll need, along with my kitchen notes. Full measurements are in the recipe card below.
- Onion, garlic, and celery. My mom calls these the non-negotiables of a good pasta sauce, and I don’t disagree. Finely chop them so they soften quickly.
- Extra virgin olive oil. To sauté the veggies. I really recommend a good-quality olive oil because it makes a difference.
- Crushed tomatoes. Most grocery stores stock Italian-style crushed tomatoes, which are ideal, but plain crushed tomatoes will also work. Just make sure there is no added sugar. You can also blend up my fire roasted tomatoes to use in place of the crushed ones.
- Allulose (or keto sweetener of choice). You may or may not need this, depending on how sweet the tomatoes are. I find just a pinch balances the tomatoes’ acidity.
- Basil. Fresh basil is preferred, but dried can also work. If you use the latter, use about 1/3 of the amount, as it’s more concentrated.
- Salt and black pepper. To taste.
How to make keto spaghetti sauce
Step 1- Combine ingredients. Add olive oil to a large pot over medium heat. Once hot, add the veggies and cook until tender. Add the remaining ingredients and bring to a boil.
Step 2- Simmer. Once boiling, reduce the heat to low, cover, and simmer for 40 minutes.
Step 3- Serve. Remove the sauce from the heat and serve.
Arman’s recipe tips
- Make a smooth sauce. Once it’s done simmering, let it cool slightly, then blend everything until smooth. Don’t forget to vent the lid!
- Make a meat sauce. Add 1 lb ground beef, chicken, or your preferred protein, and cook fully before adding the tomatoes. If it’s a higher-fat cut, drain the excess fat. If you’re using chicken or turkey, I like to add 1 tablespoon more olive oil.
- Make a pink sauce. Right before serving (and on low heat), stir in 2-4 tablespoons of heavy cream and 1/4 cup of freshly grated Parmesan cheese.
- Prefer a thicker sauce? Simmer for an extra 15-30 minutes uncovered.
Storage instructions
To store: Store the pasta sauce in an airtight jar in the refrigerator for up to two weeks.
To freeze: Place leftover sauce in a shallow container and freeze it for up to 6 months.
Reheating: Simmer in a pan over medium heat or microwave until warm.
What to serve with this recipe
Serve my low-carb pasta sauce with just about anything! Here are some ideas:
- Baked into zucchini boats or spaghetti squash
- Over zucchini noodles, keto pasta, almond flour pasta, shirataki noodles, or keto gnocchi
- Layered in keto lasagna, on a keto pizza, or in a keto pizza casserole
Keto Spaghetti Sauce
Ingredients
Instructions
- In a large saucepan, add the olive oil and place it over medium heat. Once hot, add the onion, celery, and garlic and cook until tender. Add the remaining ingredients and bring to a boil. Once boiling, reduce heat the low, cover, and reduce to low heat. Let the sauce simmer for 40 minutes.
- Remove the sauce from the heat and serve immediately, or let it cool completely.
How many ounces do you consider for a serving size for the keto spaghetti sauce?!
Hi Tina, this will depend a lot on how much you reduce the sauce during cooking. I would estimate that a single serve would be around 4-5 oz for a standard amount of sauce. Hope this helps!
Thank you for sharing this homemade recipe for pasta sauce. I have been on keto for a short time but I love your recipes. ❤️
You are so welcome, Rebecca. I’m glad you enjoyed this recipe. I hope you’re finding the keto diet easy to stick to!
This was really good, but I wish you had metric measurements.
Hi Ash- I hear you. I’m making an effort to go through every single post and re-test them to provide metric measurements. Thanks for your patience.
Super easy to make. My husband and I love it with zucchini spaghetti. Also made zucchini boats. Double YUM! Great sauce for anyone, especially those trying out Keto recipes.
I need these quantities to be biggie-sized. I want to preserve it for later. There must be an app out there that converts easily.
Hi Robin, in the recipe card at the bottom of the page, if you click the “2x” or “3x” button it will double or triple the quantities for you so that you can scale up the recipe easily. Hope this helps!
Really yummy sauce, I just wish I had more.
Thanks for the review, Pamela. It’s a great sauce, isn’t it!
Tripled the recipe and made some for the freezer. Excellent!
This sauce was absolutely delicious! I have made a bunch of your things, but this was my first keto and did not disappoint 👏🏻
Thanks so much Susan! I’m so glad you’ve found so much success with my recipes. It means the world that you took some time to leave a comment.
I needed this!
So glad to be of help Dee!
Thank you for this recipe. I am wanting to use my home grown tomatoes and make it in big batches. Do you know if I need to change anything in order to can it?
Hi Susan- Wow, home grown tomatoes would work so well in this. I’d reduce the amount to about 40 ounces. Crush or blend the tomatoes down into a thick puree and measure out 54 ounces (you shouldn’t have too much leftover). I actually like the peel (it will break down as it cooks), but you can start with peeled tomatoes first.
Thank you
We started a keto diet last week and I was craving spaghetti. This sauce is perfect!!!!! Made exact as the recipe and my husband and I both love it. Thanks for sharing. This is going to be a staple!
I made this tonight and it was awesome!
Thanks for posting this. It is going to be a regular at my house. Game changer!!!!
Made this yesterday to go with the Eggplant Lasagna. We loved it but…..I ended up using more spices for us. (2T Italian Seasoning, 1T Garlic powder, 1T crushed red pepper and 1T dried parsley). Still a great and fast recipe to make. 🙂
I swapped out bell peppers for the tomatoes and it didn’t taste like spaghetti sauce. v
Hi Shawn- I’m not surprised it didn’t turn out like regular spaghetti sauce- Tomatoes add sweetness and richness, and also the authentic ‘spaghetti sauce’ flavor. Unfortunately, bell peppers would need quite a hefty seasoning mix added to remotely replicate it.
Delish! Thank you so much for this recipe! ❤️ Love the fact you can take it low carb veggie all the way, or add burger if you want. A very versatile recipe for sure 😊
Can I use fresh tomatoes, not canned?
of course you can- It will taste so much better, too 🙂
Where is the portion size? 1/4 cup? 1/3 cup?
1/2 cup 🙂