Preheat your oven to 350.

Pour in the shortening, sugar, brown sugar, eggs, vanilla, baking soda, cinnamon, and salt in a large mixing bowl and mix on medium speed until completely combined.

Add in the flour 1 cup at a time on low speed.

Once everything is mixed, scoop spoonfuls onto a cookie sheet and indent the center with your thumb. Fill the center with a little spoonful of blueberry butter and fold dough over top. You don't want to over fill these or the dough won't close and seal and the butter will just ooze out when baking.

Bake at 350 for about 15 minutes or until they are a nice golden brown color.

Once the cookies are done, lay them on a towel to cool.

Whip the butter on medium speed until it's fluffy.

Add in the powdered sugar, cinnamon, and vanilla on low speed until its completely combined. Then turn it up to medium/high speed and let the mixture whip for about 30 seconds.