Place all the ingredients in a slow cooker and cook on LOW for 8-10 hours or on HIGH for 5-6 hours. Use an immersion blender (or transfer to a countertop blender) and puree until smooth.

Leave the lid of the slow cooker open and continue to simmer on LOW for 6+ hour, or on HIGH for 4+ hours, or until the pear butter has thickened to the desired consistency.

Taste the pear butter and if you prefer it sweeter add some more brown sugar and let it simmer for another 30 minutes or so.

Optional: Pears tend to be a little gritty. For a smoother taste, process the pear butter in a food mill.

If you're not canning the pear butter, it will store in the fridge for about 2 weeks.

To can for long-term storage: Ladle the hot pear butter into sterilized jars and screw on the washed lids and rims. Process in a boiling water bath for 10 minutes. Remove and let sit undisturbed for 24 hours before moving the jars. Store in a dark, cool place for up to a year. For best flavor consume within 4-6 months.