Best Lemon Buttercream Frosting. 2 Gradually add powdered sugar one cup at a time beating well on medium speed. Add lemon juice and zest.
In a large bowl cream shortening and butter with an electric mixer until light and fluffy. Use immediately or cover and refrigerate for up to 3 days. Add lemon juice and zest.
Scrape the bowl down with a rubber spatula.
In a large mixing bowl with the paddle attachment if using a stand mixer beat together the sugar butter lemon zest and salt until smooth and creamy about 1-2 minutes. Reduce speed to medium-low. Add the lemon juice and vanilla. An old fashioned lemon cake recipe.