• Chop the tomatoes and onions into chunks.
• Add the tomatoes, onions, and garlic to a slow cooker and cook for 12 hours over low heat.
• There will be puddles of liquid sitting around the vegetable chunks. Use a ladle to strain off the water. (You can discard the liquid or save it for flavoring other dishes.)
• Puree the tomatoes in a blender, foley mill, or immersion blender.
• Run the puree through a sieve to remove any solids. 
• Add the puree and all of the remaining ingredients to a stock pot.
• Bring the mixture to a boil and then reduce the heat to a simmer, stirring occasionally, for 3 hours or until thick. 

Canning Instructions

• Ladle the ketchup into half pint jars leaving ⅛” headspace.
• Remove the air bubbles.
• Wipe the rims and top with rings and lids.
• Process half pints (or pints) in a waterbath canner for 15 minutes.