In a large mixing bowl, beat heavy cream with a whisk (attached to a stand mixer or a handheld electric mixer) for 2-3 minutes until thickened. Slowly beat in the powdered sugar, lemon extract, lemon zest, and unflavored gelatin.
Beat an additional 2-3 minutes until desired consistency.
Frost cooled cupcakes and refrigerate for one hour. Serve cold and enjoy.
Notes
Unflavored Gelatin- A flavorless, odorless thickening agent that makes the frosting easy to pipe with a frosting bag. You could also use clearjel for this too. You can find unflavored gelatin in the Jello and pudding aisle of the grocery store!