Keto Marinara Sauce – Simple, Bright, and Low-Carb

Marinara sauce should taste fresh, clean, and comforting—without loads of sugar. This keto version keeps the classic Italian flavor while staying low-carb and weeknight-friendly. It’s rich with tomatoes, garlic, and herbs, with just the right balance of acidity and sweetness.

Use it on zoodles, baked chicken, meatballs, or as a dipping sauce for mozzarella sticks. Once you try it, you’ll probably stop buying the jarred stuff.

What Makes This Special

This marinara is designed for keto and low-carb eating without sacrificing flavor. Many store-bought sauces rely on added sugar to round out acidity.

Here, we keep it bright by cooking the tomatoes slowly and finishing with a pinch of erythritol or allulose if needed. The result is a clean, vibrant sauce that feels homemade in every bite.

It uses simple pantry ingredients and cooks in under 30 minutes, but it tastes like it simmered longer. The texture is smooth with a little body, and it’s flexible: leave it chunky or blend it silky.

It also freezes beautifully, so you can meal prep a batch and have sauce ready whenever you need it.

Shopping List

• Olive oil: 2 tablespoons
• Garlic: 4–6 cloves, minced
• Crushed tomatoes (no sugar added): 1 can (28 ounces)
• Tomato paste (no sugar added): 1 tablespoon
• Onion: 1 small, finely diced (optional for strict keto; see notes)
• Dried oregano: 1 teaspoon
• Dried basil: 1 teaspoon (or use fresh at the end)
• Red pepper flakes: 1/4 teaspoon (optional for heat)
• Bay leaf: 1
• Sea salt: 1 teaspoon, plus more to taste
• Black pepper: 1/2 teaspoon, freshly ground
• Sweetener (erythritol or allulose): 1/2–1 teaspoon, to taste
• Fresh basil: Small handful, chopped (optional but excellent)
• Butter: 1 tablespoon (optional for extra richness and lower acidity)

Step-by-Step Instructions

1. Warm the oil: Set a medium saucepan over medium heat and add the olive oil. Give it a minute to shimmer.
2. Sauté aromatics: Add the garlic (and onion if using). Cook 1–2 minutes, stirring often, until fragrant. Do not brown the garlic; if it starts to color, lower the heat.
3. Build the base: Stir in tomato paste and cook for 30 seconds.
   

   This wakes up the flavor and deepens the sauce.

4. Add tomatoes and spices: Pour in the crushed tomatoes. Add oregano, dried basil, red pepper flakes, bay leaf, salt, and black pepper. Stir to combine.
5. Simmer gently: Bring to a light simmer, then reduce heat to low.
   

   Cook uncovered 15–25 minutes, stirring occasionally. The sauce should thicken slightly and taste more rounded.

6. Adjust acidity: Taste. If it’s sharp, add 1/2 teaspoon sweetener and the butter.
   

   Stir and taste again. Add more sweetener in small amounts until the acidity balances without becoming sweet.

7. Finish with freshness: Remove the bay leaf. Fold in fresh basil if using. For a smoother sauce, blend with an immersion blender for 5–10 seconds.
8. Final seasoning: Add more salt and pepper if needed.
   

   The sauce should taste bright, savory, and clean.

Keeping It Fresh

Store in an airtight container in the fridge for up to 5 days. The flavors often improve by day two. If you see separation, just stir or reheat gently and whisk it back together.

For longer storage, freeze in 1–2 cup portions for up to 3 months.

Ice cube trays or silicone molds are great for small servings. Reheat from frozen over low heat with a splash of water or broth.

Benefits of This Recipe

• Low in carbs: No added sugar and careful seasoning keep carbs down.
• Quick and manageable: About 30 minutes from start to finish.
• Budget-friendly: Pantry ingredients, no fancy steps, and easy to scale.
• Versatile: Works with zoodles, spaghetti squash, meatballs, chicken parm, or as a base for shakshuka.
• Meal prep ready: Freezes well and reheats smoothly.

Common Mistakes to Avoid

• Using tomatoes with added sugar: Check labels. Many canned tomatoes and sauces sneak in sugar.
• Burning the garlic: Bitter garlic will overpower the sauce.
  

  Keep heat moderate and stir.

• Skipping salt: Salt rounds out acidity and brings out sweetness naturally. Taste as you go.
• Over-sweetening: Add sweetener in tiny increments. You want balance, not a dessert vibe.
• Cramming in too many herbs: Keep it simple.
  

  A clean oregano-basil profile tastes classic and fresh.

Recipe Variations

• Chunky garden style: Add diced zucchini, mushrooms, or bell pepper. Sauté with the onions to soften. Keep portions small to stay low-carb.
• Arrabbiata: Increase red pepper flakes to 1 teaspoon and add a minced Calabrian chili for heat.
• Rosé sauce: Stir in 2–3 tablespoons heavy cream at the end for a silky pink sauce.
• Herb-forward: Finish with a mix of fresh basil, parsley, and a touch of thyme for a brighter, fresher flavor.
• Meaty marinara: Brown 1/2 pound ground Italian sausage or beef first, drain, then build the sauce in the same pot.
• Dairy-free richness: Swap butter with a tablespoon of extra-virgin olive oil and a splash of almond milk to soften acidity.

FAQ

Is marinara sauce keto?

Yes, as long as it has no added sugar and you watch the portion size.

Tomatoes have natural sugars, but in reasonable amounts, this sauce fits comfortably in a keto plan.

Can I skip the onion to lower carbs?

Absolutely. The onion adds sweetness and body, but you can omit it and rely on garlic, herbs, and a small pinch of sweetener. If you skip onion, consider a longer simmer for depth.

Which canned tomatoes are best?

Look for high-quality crushed tomatoes with only tomatoes and salt on the label.

San Marzano-style tomatoes often have the cleanest taste and fewer off-flavors.

Do I need sweetener?

Not always. Taste after simmering. If the sauce is sharp, a tiny amount of erythritol or allulose can balance it.

Add in 1/4 teaspoon increments to avoid over-sweetening.

How can I thicken the sauce without carbs?

Simmer uncovered to evaporate excess liquid. A brief blend with an immersion blender also thickens naturally by breaking down tomato fibers.

What can I use this sauce for?

Try it with zucchini noodles, spaghetti squash, meatballs, grilled chicken, eggplant, or as a base for shakshuka and baked eggs. It also makes a great dipping sauce for low-carb mozzarella sticks.

Can I make it in a slow cooker?

Yes.

Sauté garlic (and onion) on the stove first, then transfer to a slow cooker with the rest of the ingredients. Cook on low for 3–4 hours. Finish with butter and fresh basil.

How do I reduce acidity without sweetener?

Add a tablespoon of butter or a splash of olive oil, simmer longer, or use a pinch of baking soda.

If using baking soda, start with 1/16 teaspoon; too much dulls the flavor.

Is this sauce spicy?

Only if you add red pepper flakes. It’s mild by default. Adjust heat to your taste.

Can I double the recipe?

Yes.

Use a larger pot and extend the simmer slightly to reduce properly. Taste and adjust salt and sweetener at the end.

In Conclusion

Keto Marinara Sauce doesn’t need sugar to taste great. With good tomatoes, a gentle simmer, and simple herbs, you get a sauce that’s bright, balanced, and versatile. Make a batch on Sunday, freeze a few portions, and you’ll have a fast, flavorful base ready for weeknight meals. It’s the kind of staple that makes low-carb cooking feel easy and satisfying.