Prepare Blueberries: Begin by combining fresh blueberries and granulated sugar in a medium saucepan. Cook over medium heat, mashing the blueberries with a potato masher as they soften.
Cook Down: Allow the mixture to simmer for 8-10 minutes. You'll know it's ready when it thickens into a jam-like consistency, full of that gorgeous blueberry color.
Cool the Puree: Once thickened, remove from heat and let the blueberry puree cool to room temperature. To speed this up, you can pop it in the fridge for a few minutes.
Beat Cream Cheese and Butter: In a stand mixer, beat together the softened cream cheese and salted butter until fluffy and creamy. This will give your frosting a rich texture.
Incorporate Sugar: Gradually add in the powdered sugar while mixing on low speed, then increase to medium-high. Continue mixing until the frosting is thick and smooth—about 3-5 minutes.
Add Vanilla and Blueberry: Gently fold in the vanilla extract, followed by the cooled blueberry reduction. Mix until everything is beautifully combined and has that stunning, vibrant hue.
Frost Your Treats: Transfer the luscious frosting to a piping bag and get ready to frost your favorite cupcakes, cakes, or even bundt cakes.