In a large bowl or saucepan sprinkle peaches with brown sugar and lemon juice and let sit while gathering the remaining ingredients.
In a large heavy bottom saucepan combine peach mixture, pectin, cinnamon sticks and butter to keep foam down.
Cook over high heat stirring frequently to prevent scorching about 15 minutes or until full rolling boil.
(OPTIONAL) Use a submersion blender or a potato masher if small pieces are desire.
Avoiding the cinnamon sticks.
Stir in white sugar.
Return to a full rolling boil. Boil hard for (3) minutes stirring constantly.
Remove from heat and add Southern Comfort and vanilla extract. Remove cinnamon stick.
Skim off foam. Ladle in hot sterilized jars leaving 1/4 inch head space, wipe rims and place lids and screw top on.
Place in a hot water bath covering by 1 inch of water.
Process in boiling bath 10 minutes. Shut heat off and let sit in water bath 5 more minutes. Then remove the jars from the hot water without tilting and set aside to cool.
Leave for 12 hours then check the seals on the jars by pressing on the centers of the lids. If the lids do not spring back, they are vacuum sealed and the jam can be stored at room temperature. Another way to check is to remove the ring and try to lift the lid.
If it lifts up, it wasn't sealed properly.
If the lid flexes, there is no seal, so store the jar in the refrigerator.