In a medium, heavy-bottomed saucepan, gently reduce the Prosecco over medium heat until you have about a Tablespoon left. Set aside to cool.
Dump all the ingredients in the bowl of a stand mixer.
Beat on low at first, incorporating the powdered sugar. Once it's combined, beat on medium to medium-high speed until desired consistency is reached.
Store in the refrigerator up to one week or in the freezer for up to 3 months.