Instructions

1. Our Raspberry Frosting starts with a 6 oz. clamshell of Fresh Raspberries which is approximately 1 cup of raspberries.  If you can't find fresh, frozen will also work.
2. Place the cup of raspberries in a food processor and purée them.
3. Run the puréed raspberries through a sieve to remove the seeds.
4. Add the butter and 1/3 cup raspberry purée to a mixing bowl. (Keep the rest of the raspberry purée to add later if the frosting needs more liquid.) The butter should be what we call “slightly softened” which is somewhere in between straight out of the refrigerator and room temperature.
5. Mix the butter and purée until they are completely combined (about 3 minutes.) Stop halfway through and scrape the butter/raspberry mixture off the mixing paddle and the sides of the bowl.
6. Add the powdered sugar to the butter/raspberry mixture in the mixing bowl.  
7. Start your mixer (or electric beater) on the lowest setting. (Two Sisters Tip: place a clean dishtowel around your mixer to keep the sugar from flying out.)  Keep on low until the butter and sugar are incorporated (about 30 seconds), remove the dishtowel, and scrape down the sides of the bowl. Increase the mixer speed to medium-high and mix for 30-45 more seconds until the frosting starts to be light and fluffy.
8. If the frosting is too thick at this point, add more raspberry purée and mix again.  This frosting is a little looser than a typical buttercream because of the fresh fruit but it will firm up in the refrigerator.  The raspberry flavor will also deepen after sitting in the refrigerator overnight so this is a good frosting to make ahead and frost the next day. If after some time in the refrigerator, the frosting is still too "wet”, add 1/2 cup additional powdered sugar. Keep adding powdered sugar 1/2 cup at a time until you have the frosting at the desired consistency.