Step 1

Add fresh blueberries to the pitcher of a blender and process until smooth.

Step 2

Add pureed blueberries, sugar, cinnamon, lemon juice and lemon zest to a 6 quart or larger slow cooker and stir to combine.

Step 3

Cover and cook on LOW for 1 hour.

Step 4

Prop lid of slow cooker up with a wooden spoon or other heat-safe kitchen utensil to allow excess liquid to evaporate.

Step 5

Continue cooking on LOW for an additional 4 to 5 hours checking on the blueberry butter every hour or so to see how thick it is.

Step 6

Blueberry butter is done when it mounds nicely on a spoon and does not easily run off the spoon.

Step 7

Once thickened, Ladle blueberry butter into a 1-pint canning jar or food storage container and store in the refrigerator for up to 2 months or in the freezer for up to 1 year.