Combine Ingredients: Using a standing mixer, combine all ingredients and mix with the whisk attachment until combined and smooth. Ensure the butter is properly softened to avoid lumps, and add the diced strawberries gradually to incorporate them evenly throughout the frosting.
Adjust Consistency: If the frosting is too thin, add in an extra 1/2 cup of powdered sugar and continue mixing until thick. The perfect consistency should hold its shape when piped but remain smooth and spreadable.
Store Properly: Scoop the finished frosting into a container with a sealed lid and place into the refrigerator for up to 1 week or in the freezer for up to 3 months. Proper storage ensures the frosting maintains its flavor and prevents it from absorbing other odors.
Prepare for Use: Before using for cupcakes or to frost a cake, allow to thaw to room temperature and beat again to make creamy and thick. This reactivates the texture and makes the frosting easier to work with.