The "How to" on Home Canned Ketchup

This is how I make my ketchup.  

I do not peel my tomatoes because I use a sauce maker (you could also use a food mill).  Wash, trim and slice up 10 pounds of paste tomatoes.  I simply cut my paste tomatoes in 4th's and toss them in the pot.

I make a spice bag that includes 2 bay leaves, 2 Tbsp. celery seed, 2 tsp. whole allspice, 1 tsp whole cloves, and 1 tsp. black peppercorns. 

I place half of the cut tomatoes into a large pot, along with the spice bag.  I cook them down.

I then add the other half of the tomatoes, along with 2 cups of diced onions (I typically don't measure, and use 2 large ones).

After about 1 to 1 1/2 hours of cooking, I discard the spice bag, and run the mixture through my sauce maker.   This removes the seeds, tomato skins, etc. 

(Just out of the sauce maker)

I return the mixture to a clean pot on the stove, adding 2 cups of granulated sugar, 2 Tbsp. pickling/canning salt, and 2 cups of organic Bragg's apple cider vinegar.  I bring it to a boil, then reduce heat to reduce the mixture to a thickness I like.  The amount of time it takes to reduce can be 2 1/2 hours or more, depending on the temperature you use on your stove top.  If it's too high, your ketchup will stick to the bottom of the pot and burn.  I use one notch up from medium heat (again I have a very old stove, so this can vary).  I stir it often, as it reduces.

 (reduced and ready to can)

I then ladle it into hot sterilized 1/2 pint jars (about 5-6) depending on how thick you like it), wipe rims, and seal in a canner pot for 35 minutes (starting the timer when the water comes back to a boil).  Leave a 1/2 inch head space.  I remove the lid, and lift up the jars but leave them in for another 5 minutes before placing them on a thick towel for 24 hours.

Once jars are opened they must be refrigerated.  This doesn't last very long after opening, so if you have a smaller need, than can it in smaller jars.