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Simple Roasted Crockpot Tomato Sauce Recipe

This Roasted Crockpot Tomato Sauce is made from scratch, flavorful and packed with nutrition. Eliminate the added sugars, fillers and preservatives that are often found in store bought brands.

This sauce is Slow cooked in your crockpot with fresh roasted tomatoes, veggies, fresh basil, balsamic vinegar and plenty of garlic. Our crockpot tomato sauce has a rich hearty flavor profile that we know you will love.

After a bit of prep work you can set it and let it simmer in your crockpot all day. Use this full bodied red sauce in lasagna, spaghetti dinners, creamy raviolis and even as a pizza sauce.

Roasted Crockpot Tomato Sauce
Roasted slow cooker tomato sauce is made with fresh vegetables to your own taste. This sauce is long simmered in a slow cooker for the best flavor!

What does roasting do to vegetables?

Roasting vegetables creates a deeper flavor and enhances the natural flavors of each veggie, drawing out the moisture and cooking the exterior to a crispy golden brown.

By roasting vegetables you can enjoy them in a variety of ways, either on their own as a side dish, paired with pastas and meats for a nutritious, flavor packed meal, or blended into a sauce which is our favorite way to use up extra vegetables.

This crockpot tomato sauce is a fantastic way to use up your garden harvest.

Roasted Crockpot Tomato Sauce In A White Bowl.
Roasted Vegetables are pureed and long simmered to make this crockpot tomato sauce deeply flavorful.

Does Roasting Tomatoes Remove the Acidity?

Tomatoes are a highly acidic veggie making them difficult for some people to digest and enjoy. They often contribute to heartburn and acid reflux. Unfortunately roasting your tomatoes won’t make them less acidic.

Tomatoes acidity range from 4.1 to 4.6 for most varieties. If you struggle with heartburn or acid reflux it’s best to opt for other less acid sauces such as pesto or white cream sauces.

Things you can do to mask or slightly reduce the acidity of tomato sauces.

  • Put a few carrots into the roasted vegetable mix. One to two carrots will help balance the acid in the tomatoes.
  • Use Vidalia sweet onions rather than a stronger white or yellow onion. This will also mellow the acid in the final sauce.
  • Add a pinch of baking soda (not too much or your sauce will taste bitter) to counteract the acidity of your finished tomato sauce.
  • Adding sugar to tomato sauces is another technique used to reduce the acidity though it’s not something we choose to do.

You can add milk or cream to your sauce, this will mellow out the boldness of the acidity and mask it slightly.

Garden Harvested Roma Tomatoes And Peppers
Garden grown San Marzano Tomatoes and fresh peppers used in this crockpot tomato sauce recipe.

Homemade recipes like this are unique and easily tailored to your family’s tastes. We are especially fond of roasting vegetables to enhance their flavors. Try our roasted vegetable recipe for an easy and healthy side dish.

If you’re Looking for more ways to use up fresh tomatoes these recipes are all winners.

How do you freeze Crockpot tomato sauce?

All homemade sauces freeze very well and can be available year round by making extra and setting some aside in your freezer. Follow these steps to store all of your scratch made sauces.

  • Complete the roasted tomato sauce recipe as directed.
  • Let the sauce cool to room temperature.
  • Pour the sauce into quart sized Ziplock freezer bags or other freezer safe containers.
  • Label with the recipe name and date.
  • Freeze for 3-4 months.
Roasted Slow Cooker Tomato Sauce
If your not a gardener find a local farmers market. Join a CSA or food Co-op. Bring the best organic produce into your family’s diet.

Recipe Notes:

This crockpot tomato sauce is simple and so rich and creamy! All it takes is a little bit of planning and few hours in your crockpot to simmer to perfection. You will roast the fresh tomato-vegetable mixture for about an hour.

Then blend it all up and transfer it to your slow cooker for the rest of the afternoon. Simple! And your house will smell fantastic all day.

First, preheat your oven to 425 degrees F.

Preparing the Vegetables:

  • Chop your tomatoes. Roma tomatoes are an excellent choice for sauces.
  • Quarter them and lay them down in the pan.
  • Rough chop your onion, dropping the pieces over top of the tomatoes.
  • Chop peppers and arrange them in your baking dish with the onion and tomato chunks.
  • Add your whole cloves of garlic. Place them among the onions, peppers and tomatoes.
  • Tear a few fresh basil leaves and sprinkle them around.
  • Drizzle the mixture with some olive oil, sea salt and fresh ground pepper.
  • Using your hands, mix it all around to coat everything.

The Roasting Process:

Place the prepared vegetables in your preheated oven for 45 minutes to an hour.

Your home will smell incredible while these veggies roast.

Roasted Slow Cooker Tomato Sauce
Beautifully crisp roasted veggies

Puree the Vegetables:

  • Once all are soft and slightly caramelized cool them and blend into a puree.
  • Spoon the roasted vegetables into your food processor or blender. (do this in small batches if necessary)
  • Add the can of tomato paste and 1 tablespoon of balsamic vinegar.
  • Blend to a smooth, creamy consistency. You can add some of the juices from the baking dish if you would like to thin it out.

If you don’t have a blender or prefer not to use one you can run the finished sauce through a foly food mill once it is finished slow cooking. The result is the same. A yummy smooth rich crockpot tomato sauce.

Roasted Slow Cooker Tomato Sauce
Crockpot tomato sauce

Slow Cook:

Any slow cooker will work. Today there are so many different multi cookers in our kitchens. If they slow cook you can make this recipe in them.

Instant Pot Tomato Sauce:

To make this pasta sauce recipe in your instant pot. Use the slow cook function and follow the instructions in this recipe exactly.

I use my instant pot for slow cooking, I recommend cooking on medium heat as they cook slightly lower than most crock pots.

Finishing:

At this point add any extra spices you prefer. We love extra oregano and a bit of dried rosemary. 

The basil and garlic are the mvps of this recipe.

Additional ideas for this recipe

  • Add browned meat to your slow cooker when you pour in the roasted puree.
  • Add 1 pound of browned Italian sausage to the cooker. We enjoy sausage in our 5 Cheese Homemade Lasagna.
  • Ground beef or ground turkey also make nice additions to this slow cooker tomato sauce. 
  • Add chopped mushrooms or spinach in the last hour of simmering to bump up the texture and nutritional benefits.
  • Refresh any dried spices in the last 30 minutes of simmering to keep the flavors powerful.
  • Red pepper flakes, fresh rosemary leaves and fresh oregano all make great enhancements to this recipe.
Roasted Slow Cooker Tomato Sauce

Our family enjoyed this over whole grain pasta for a simple, filling dinner.

Your Printable Recipe Card:

Roasted Slow Cooker Tomato Sauce
Yield: 10 servings

Roasted Tomato Sauce-Slow Cooker Method

Prep Time: 15 minutes
Cook Time: 7 hours
Total Time: 7 hours 15 minutes

Roasted Slow Cooker Tomato Sauce method punches up the flavor on homemade tomato sauce. Roasting veggies concentrates their flavor. Long simmering the sauce keeps it simple and really blends the flavor together.

Ingredients

  • 12 Ripe Tomatoes (Roma type preferred but any variety will work)
  • 2 ripe peppers (any type or heat you prefer)
  • 1 Onion
  • 10 cloves of Garlic
  • 1/4 cup chopped Fresh Basil (several fresh leaves)
  • 1 tsp. Sea Salt and fresh ground Pepper
  • 1 Tablespoon Olive oil (as needed)
  • 1 6 oz. can of Tomato paste (use two cans if sauce is too juicy)
  • 1 Tablespoon Balsamic Vinegar

Instructions

  1. Preheat your oven to 425 degrees F

CHOP:

  1. Chop the Tomatoes. They can be any kind but ripe Roma tomatoes have the best texture for sauce.
  2. Deseed and Chop your peppers into one inch chunks
  3. Quarter the tomatoes and peppers and lay them down in a shallow oiled 9 x 13 baking dish pan.
  4. Rough chop the onion. Drop the onion pieces over top of the tomatoes and peppers.
  5. Add the whole cloves of garlic. Sprinkle them among the onions, peppers and tomatoes.
  6. Tear a few fresh basil leaves and sprinkle them around.
  7. Drizzle the mixture with some Olive oil, Sea Salt and fresh ground Pepper.
  8. Using your hands, mix it all around to coat everything.

ROAST:

  1. Place the pan of vegetables in your preheated oven for 45 minutes to an hour.
  2. Revel in how amazing it all smells.
  3. Once the vegetables are soft and slightly caramelized remove from oven.
  4. Cool until you can handle the vegetables to transfer them to blender.

BLEND:

  1. Place the roasted vegetables into your food processor or blender. Add the can of Tomato paste and the 1 Tablespoon of Balsamic Vinegar.
  2. Pulse or blend to a smooth, creamy consistency. You can add some of the juices from the baking dish if you would like to thin it out.

SLOW COOK:

  1. Transfer the sauce to your crockpot and cook on low for 4-6 hours.
  2. At this point add any extra spices you would like. I added some Oregano a bit of dried Rosemary and some more Pepper.
  3. You could also cook up and add your meat to your crock pot if you are wanting to make it a meat sauce.

Notes

The type of tomato you are using determines how juicy the sauce is. I say 12 tomatoes since that is what I used. I used Arbason tomatoes which are a slicing tomato rather than a thicker fleshed roma type. For Romas you will get a thicker sauce and will have room for many more tomatoes. Poundage is difficult to guess since all tomatoes varieties will give you different weight by volume.

The tomato paste is also a guess for the same reason. Use two cans if you are using juicy tomatoes or if you prefer a thicker sauce.

Nutrition Information

Yield

10

Serving Size

1

Amount Per Serving Calories 71Total Fat 2gSaturated Fat 0gTrans Fat 0gUnsaturated Fat 1gCholesterol 0mgSodium 257mgCarbohydrates 13gFiber 4gSugar 7gProtein 3g

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Homemade Roasted Tomato Sauce is intensely flavorful. This Crockpot tomato sauce punches up the flavor on homemade tomato sauce.

Follow Us:

We enjoy meeting you on our social networks. Follow us on Facebook, Pinterest, Instagram . Tag us with your pictures of our recipes and comment on how it went for you. We would love to see what you do with them.

We often like, comment and share your posts of our recipes on our daily Instagram stories.

Ask questions and rate the recipe in the comments section below. Please share what you did with this recipe. We are always looking for more and better ways to make homemade food. Other cooks love your ideas!

Recent Posts:

Loretta hopman

Tuesday 11th of October 2022

one can of tomato paste you say for this tomato sauce recipe. 6 oz, 8 oz, or 12 oz can of paste.

and it would be good if we have the poundage for tomatoes rather than how many. We can't go wrong with weight measures, thank you.

Diane

Wednesday 12th of October 2022

Hi Loretta, The type of tomato you are using determines how juicy the sauce is. I say 12 tomatoes since that is what I used. I used Arbason tomatoes which are a slicing tomato rather than a thicker fleshed roma type. For Romas you will get a thicker sauce and will have room for many more tomatoes. Poundage is difficult to guess since all tomatoes varieties will give you different weight by volume. Try five pounds and adjust to fit your pan? The tomato paste is also a guess for the same reason. Use two 6 oz. cans if you are using juicy tomatoes or if you prefer a thicker sauce. Feel free to adjust the recipe to suit yourself. That is what homemade cooking is all about. We'd love to know how it turns out for you. Thanks for the question and have a great day!

Aus dem Slowcooker: Ofengeröstete Tomatensauce

Saturday 13th of August 2022

[…] und der Paprika-Tomatensauce geht es ja auch ohne das vorherige Anrösten. Aber wenn einem das Originalrezept doch eine besonders “full bodied, intensely flavored” Tomatensauce verspricht, dann […]

Linda

Wednesday 11th of August 2021

How do you store the finished Roasted tomato sauce? Frozen? Canned?

Diane

Wednesday 11th of August 2021

Hi Linda,

This sauce will hold in the fridge in an airtight container a week or more in good conditions. You can freeze this sauce in air tight freezer bags or containers for up to 6 months.

If you need canning instructions and a canning tested recipe for roasted tomato sauce Here's one that comes from a food blogger I trust..

Hope this helps! Have a wonderful day.

Leann

Wednesday 28th of April 2021

Can you use frozen tomatoes for this recipe?

Diane

Wednesday 28th of April 2021

Hi leann, I believe frozen tomatoes would work fine in this recipe. Just peel them before you use them. Please let us know how it goes for you!

Lori

Friday 27th of December 2019

The recipe does not indicate when to add the peppers

Diane

Saturday 28th of December 2019

Hi Lori, Thank you so much for pointing this out. I have updated the recipe for you. Have a great weekend!

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