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How To Make Ketchup From Fresh Tomatoes In A Slow Cooker

Ever since we learned how to make ketchup from fresh tomatoes, we have been using it on and in everything imaginable!

Of course we use it quite often as a condiment. From hot dogs, hamburgers, and French fries, we seem to go through a bottle of it in no time.

how to make ketchup from fresh tomatoes
Making ketchup from fresh tomatoes is easy and much healthier for you than store-bought ketchup!

However, we also use it in our meatloaf, sloppy Joes, and homemade baked beans recipes.

So when we find ourselves with extra tomatoes from the garden, we get to work and make homemade ketchup!

Why Make Your Own Ketchup?

But you may wonder why you would want to make your own ketchup? It is fairly inexpensive and is easy to find at any grocery or convenience store.

However, have you ever looked at the ingredients label on those popular ketchup bottles that you purchase?

paste tomato
Paste tomatoes, like this San Marzano variety make the best ketchup.

High Fructose Corn Syrup is still being used and is listed as one of the main ingredients in most brands. So in an effort to eat healthier, but still maintain that great ketchup flavor, we decided a few years back that we would make our own.

We have tried different methods and different combinations of various ingredients to establish the same consistency and flavor of the store-bought varieties. This recipe produces that familiar taste and texture that we are all used to eating.

And don’t worry. If you don’t have enough fresh tomatoes to make homemade ketchup you can also make it from canned crushed tomatoes.

We have even made it using our fire roasted tomatoes to give our ketchup a smoky and roasted flavor. (See: How To Make Fire Roasted Tomatoes).

San Marzano cut
The best part about this ketchup recipe is that you don’t have to remove the skins or seeds!

Best of all, you can make it right in your slow cooker. No more standing over a hot stove for hours waiting for it to reduce and thicken.

So the next time you go to put ketchup on your hamburger, hot dog or French fries – make sure it is your own!

You can even get some glass ketchup bottles, make your own label – and REALLY impress your friends!  See : Glass Condiment Bottles

Homemade Ketchup Recipe

INGREDIENTS:
4 lbs. paste tomatoes, stems removed and cut into quarters*
1/3 cup honey (or 2/3 cup white sugar)
3/4 cup distilled white vinegar
1 teaspoon onion powder
1/2 teaspoon garlic powder
1 3/4 teaspoons salt
1/8 teaspoon celery salt
1/8 teaspoon mustard powder
1/4 teaspoon finely ground black pepper
1/4 teaspoon cayenne pepper powder
1 whole clove

pureed tomatoes
Place the cut tomatoes in a food processor or high speed blender to puree.

INSTRUCTIONS:

Place quartered tomatoes into a high speed blender or food processor and puree (skin and seeds still on the tomatoes). Pour tomatoes into slow cooker.

Add honey/sugar, vinegar, onion powder, garlic powder, salt, celery salt, mustard powder, black pepper, cayenne pepper, and whole clove – whisk to combine.

Cook on high, uncovered, until mixture is reduced by half and very thick, stirring occasionally. This will take approximately 10 – 12 hours.

ketchup made with fresh tomatoes
Add the seasonings to the tomato puree and allow it to reduce by half.

Use an immersion blender or place the mixture no more than half full in a high speed blender, working in batches as needed, to blend ingredients.

If necessary, ladle the ketchup into a strainer and press mixture with the back of the ladle to strain out any remaining skins or seeds.

Transfer the strained ketchup to a bowl. Cool completely before tasting to adjust seasonings to taste. Add additional salt, black pepper, or cayenne pepper as desired.

reduced ketchup
Once the ketchup has reduced by half, puree the mixture one last time.

*Note – you can substitute 2 (28 ounce) cans peeled crushed tomatoes in place of the fresh tomatoes.

Enjoy!

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Mary and Jim

Homemade Ketchup Recipe

How to make homemade ketchup with fresh tomatoes in a slow cooker

  • 4 lbs. paste tomatoes (stem removed, cut in quarters)
  • 1/3 cup honey (or 2/3 cup white sugar)
  • 3/4 cup distilled white vinegar
  • 1 teaspoon onion powder
  • 1/2 teaspoon garlic powder
  • 1 3/4 teaspoons salt
  • 1/8 teaspoon celery salt
  • 1/8 teaspoon mustard powder
  • 1/4 teaspoon finely ground black pepper
  • 1/4 teaspoon cayenne pepper powder
  • 1 whole clove
  1. Place quartered tomatoes in a high speed blender or food processor (including skins and seeds) and puree until smooth. Place tomatoes in the slow cooker.

  2. Add honey/sugar, vinegar, onion powder, garlic powder, salt, celery salt, mustard powder, black pepper, cayenne pepper, and whole clove – whisk to combine.
  3. Cook on high, uncovered, until mixture is reduced by half and very thick, stirring occasionally. This will take approximately 10 – 12 hours.
  4. Use an immersion blender to blend all ingredients or working in batches place the mixture in a high speed blender or food processor. Do not fill the container more than half full.

  5. If necessary, ladle the ketchup into a strainer and press mixture with the back of the ladle to strain out any remaining skins or seeds.

  6. Transfer the strained ketchup to a bowl. Cool completely before tasting to adjust seasonings to taste. Add additional salt, black pepper, or cayenne pepper as desired.

Substitute 2 (28 oz.) cans of crushed tomatoes for the fresh tomatoes if desired. 

Canning Instructions: Place strained ketchup in a pot and heat to boiling, stirring frequently to prevent burning. Pour ketchup in sterilized half-pint or pint jars, leaving 1/2 inch headspace. Wipe the rim and add the lid and ring to finger tight. Process in a hot water bath for 15 minutes. Adjust for altitude as necessary. 

Recipe courtesy of Old World Garden Farms