I came up with this frosting to cover a lemon cake, and it was phenomenally delicious. Because there's no powdered sugar, just honey and cornstarch, it's a little softer and richer than a traditional buttercream. Make sure to use the best-quality butter and honey you can get your hands on--it will make a huge difference. —ieatthepeach
In a large mixing bowl, combine butter, honey, and cornstarch. Use an electric mixer on low speed to cream the mixture until thoroughly combined, then increase the speed to medium and continue beating until the frosting is light and fluffy.
Use the frosting immediately, or cover tightly and store in the fridge for up to 3 weeks. Bring refrigerated frosting back up to room temperature before using.