Use a hand mixer or a stand mixer with whisk attachment to make the blueberry frosting.
Cream the vegan butter until fluffy, about 3 minutes.
Then add in 1 cup of powdered sugar at a time, mixing in between.
Spoon in the blueberry jam, along with the vanilla, and continue mixing until combined. Note: If the frosting is looking like it could start to split, add in another cup of powdered sugar.
Spread onto cakes, pipe onto cupcakes, or spoon onto cookie bars!