To begin, combine all of the ingredients in a slow cooker.
Turn the slow cooker on low and prop the lid open with a wooden spoon laid across the top.
Cook for 8-10 hours, or until the mixture has reduced by almost half and thickened. (See note) Stir occasionally.
Prepare your canning supplies.
Find and discard the cinnamon stick and bay leaf.
Using and immersion blender or regular blender to purée the sauce until it is smooth.
Ladle the sauce into prepared, hot half pint jars, leaving 1/2 inch of head space.
Remove air bubbles with a bubble wand and adjust the level of butter to maintain the headspace.
Wipe the rim of the jar with a damp cloth that is dipped in white vinegar to remove any residue.
Close the jar with a lid and ring and place it into your canner. Repeat with all of the barbecue sauce.
Process your jars for 35 minutes. (Adjust for Elevation – see article linked above)
After the jars are processed, transfer them to a line surface in a draft-free location.
Allow the jars to cool for 12-24 hours.
Remove the rings, test the seals, label, and store in your pantry.
Enjoy!
Notes
If you do not reduce the sauce as much, you will get more sauce, but it will be thinner. It would make a great glaze or marinade for chicken and other meats. All other directions would be the same. You would likely just need a few more jars to can it all.This recipe can also be done on the stove top in a pot, cooking low and slow instead of in a slow cooker.