Prepare the frosting by whipping the butter until fluffy with the whisk attachment of a stand mixer. Add in the powdered sugar, half at a time, and whisk on low until combined.
Whisk in the lemon zest, lemon extract, and pinch of salt. With the mixer running on low speed, whisk in 2 tablespoons of heavy cream. Add more cream until desired consistency is achieved. Whip on high speed for several minutes until frosting is light and fluffy.