For fresh/frozen berries
Place quartered strawberries in a small saucepan over medium heat and add 1 Tablespoon of water (this will keep the berries from burning to the bottom of the pan).
Cook over medium heat, stirring frequently, until the berries release their juices, then grab a fork or potato masher and mash the berries into a pulp.
Continue to cook, stirring constantly, until mixture is reduced in volume and thickened to a thick paste (similar in consistency to tomato paste) and most of the water is cooked out.
Place in a heatproof container and let cool to room temperature before proceeding. You can speed up the process by placing the strawberry reduction in the refrigerator.
Combine softened butter, a bit of the powdered sugar (about 1 cup) and vanilla extract (if using) and salt in a large bowl and use an electric mixer to beat until creamy and well-combined. Gradually add remaining powdered sugar until it has all been added.
Scrape the sides and bottom of the bowl and add the cooled strawberry paste. Stir until completely combined, pausing to scrape the sides and bottom of the bowl as needed. Don't over-mix, but ensure all ingredients are thoroughly combined. Pipe or spread frosting onto cake or cupcakes. Enjoy!
For freeze-dried berries
Place freeze dried berries in a small food processor and pulse until they’ve become a fine powder. Set aside.
In a large bowl, combine butter, about 1 cup of powdered sugar, vanilla extract (if using) and salt until completely combined. Gradually add remaining powdered sugar until all has been added.
Add strawberry powder and stir until combined. The frosting will become stiff. Gradualy add heavy cream, one tablespoon at a time, until you’ve reached a desirable, pipe-able consistency (I typically need 3 Tablespoons of cream, but your mileage may vary and add the cream slowly).
Pipe or spread frosting onto cake or cupcakes. Enjoy!