This is a pretty involved recipe with lots of ingredients and steps. Please read through before starting. However, it is well worth the effort! I cannot eat store-bought ketchup because this is what I grew up with.
3 gallons tomatoes (rich red variety with some Roma included are best, but it’s okay to have other colors as well.)
6 small onions
3 sweet red peppers
2 Tablespoons mixed pickling spice
1 1/2 Tablespoons celery seed
3 cups sugar (can reduce and can use raw sugar or other natural sweeteners)
1 cup distilled white vinegar
1 Tablespoon sea salt
1 1/2 teaspoons black pepper
1 1/2 teaspoons ground turmeric
2 Tablespoons Clearjel or corn starch dissolved in 1/4 cup water
Method: Cook tomatoes until tender then process through a sieve. If you don’t have a sieve, peel and core the tomatoes and process in a bender in batches until smooth. Be very careful working with the hot tomatoes and juice.
Boil the juice rapidly until it is about half the volume. Literally, 2-3 hours. (Boiling rapidly helps retain color and flavor.)
After the first hour of boiling the juice, place the red peppers and onions in a blender of food processor, add a little of the juice, and process until smooth. Add the to pot of boiling juice.
Take the pickling spices and celery seed and tie into a cheesecloth and add to the pot. Add the sugar, vinegar, and salt. Continue to cook until volume is reduced to half.
Once the volume is reduced to half, add the black pepper, turmeric, and the clearjel or corn starch dissolved in water. Stir continuously until slightly thickened. Taste to see if you need to adjust seasonings to your liking.
Pour into hot prepared pint jars and seal. I usually give them a 15 minute hot water bath just to ensure a good seal.
Should yield 6 to 8 pints.