Name: Slow Cooker Tomato Sauce
Prep time: 5 min
Cook time: 240 min
Total time: 245 min
Ingredients: 2 28-ounce cans of tomatoes (crushed, whole, or diced); 1/4 cup extra virgin olive oil; 1 small onion (chopped); 2-3 garlic cloves (chopped); 1 tablespoon dried basil or Italian seasoning; 1 large carrot grated; 1 teaspoon salt; 1 tablespoon sugar

Recipe

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This simple slow-cooker tomato sauce is easy to prepare and great for pizza, pasta, calzones, and more! No peeling or seeding required.

It takes 5 minutes to place all the ingredients in the crockpot and let it do the cooking for you!

a hand holding a slow cooker tomato sauce jar

Homemade Tomato Sauce in the Slow Cooker

I’ve been making homemade tomato sauce in the slow cooker for years because my family loves the rich and delicious sauce it makes without having to babysit a pot on the stove for hours.

All you have to do is place the canned tomatoes in the crockpot (no peeling, seeding, or coring needed), add some seasonings, and heat over low for approximately 4-6 hours, and that’s it!

Depending on your slow cooker’s size, you can double or triple the batch and use the extra for all sorts of meals, freeze it, or store it for future use.

Ingredients

Tomatoes and simple seasonings are what this crockpot tomato sauce is made of. The ingredient measurements are at the end of the post, but first, let’s check where all the tasty flavors come from:

Canned tomatoes: crushed, whole, or diced. Or a mix of them!
Olive oil: adds that authentic flavor to this delicious sauce.
Onion: essential for seasoning and once cooked into the sauce, nobody will know it’s there.
Garlic cloves: I mean… flavor!
Basil: Italian seasoning also works and makes a tasty swap.
Carrot: for added nutrition and sweetens the sauce without adding a lot of sugar. Tip: you can also add other veggies like zucchini.
Salt: just enough for seasoning.
Sugar: a little to cut down the tomato’s acidity.

How to Make Slow Cooker Spaghetti Sauce

This tomato sauce is one of those crockpot effortless recipes where you simply throw everything into the slow cooker, go to do whatever you need to do, and a few hours later, the kitchen smells amazing and something delicious is waiting for you! Here are the simple steps:

Add the ingredients
Place all the ingredients into a 6-quart slow cooker.
Cook
Cover the crockpot and cook on low for 4-6 hours, stirring occasionally. If you’re using whole tomatoes, once they’ve broken down, uncover and continue cooking for another hour or two until the sauce has thickened.
Make it smooth
If you want a smooth sauce, puree it with an immersion blender or blend it in a traditional blender, in batches.

If you’ve never made it before, watch how in this quick & easy video:

How to Thicken Tomato Sauce in a Slow Cooker

If you poured the liquid from the cans or simply want a thicker sauce, you can thicken the tomato sauce directly inside the slow cooker by making a slurry in a small bowl with 2 teaspoons of cornstarch mixed with a little water. Add it to the sauce, stir to combine, and let it cook for 10 more minutes to thicken up.

How to Store Homemade Tomato Sauce

This sauce stays fresh for up to one week in the refrigerator, inside an airtight container or jar. You can also freeze portions in zip bags for up to two months. You can also make this shelf-stable and store it in the pantry by following this tomato canning process.

woman holding a jar of tomato sauce in her hand with a slow cooker in the background

How to Use Homemade Tomato Sauce

I use this slow cooker tomato sauce almost every week to make various meals like homemade pizza pockets and my kid’s favorites, Pizza Chicken, Spaghetti Squash Lasagna Boats, and meatball subs.

This sauce is also perfect for serving with classic pasta dishes, like spaghetti or this quick Skillet Lasagna. I serve it with meatballs too and oh! It’s always a must when I cook my famous Paleo Chili!

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Slow Cooker Tomato Sauce

Servings: 2 32-ounce jars

Prep Time: 5

Cook Time: 4

Total Time: 4 5

This simple slow-cooker tomato sauce is easy to prepare and great for pizza, pasta, calzones, and more! No peeling or seeding required.

5 from 15 votes

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Watch how it’s made:

Ingredients

2 28-ounce cans of tomatoes, crushed, whole, or diced
¼ cup extra virgin olive oil
1 small onion, chopped
2-3 garlic cloves, chopped
1 tablespoon dried basil or Italian seasoning
1 large carrot grated
1 teaspoon salt
1 tablespoon sugar

Instructions

Make the sauce:

Add all the ingredients into a 6-quart slow-cooker. Cover and cook 3 hours on high or 4-6 hours on low, stirring occasionally.
If you're using whole tomatoes, once they've broken down, uncover. Continue cooking for another hour or two, until the sauce, has thickened.
For a smooth sauce, blend it in a blender (in batches) or use an immersion blender to achieve the texture you like. Use in your favorite recipes.

Storage:

Allow sauce to cool down to room temperature and refrigerate unused sauce in an airtight container for up to a week or freeze for up to 2 months.

Notes

Yields 2 pints or 4 cups.

The sugar is added to cut down the acidity of the tomatoes. If you want to reduce the amount, I suggest reducing it to no less than 1 teaspoon.
If you plan on blending the tomato sauce to make it smoother, you can coarsely chop the onion, carrot, and garlic.