In a medium mixing bowl, use an electric mixer to combine the butter, orange zest, salt, and egg yolk. Beat this mixture on medium speed until it’s light and fluffy, approximately three to five minutes. You’ll notice the color lightening and the texture becoming creamy.
Next, gradually add in the powdered sugar, one cup at a time. Alternate by adding the orange juice in small increments. This method ensures that the frosting achieves the right consistency without becoming too runny.
As you mix, constantly scrape the sides of the bowl to ensure everything is well combined. Continue beating until the frosting reaches a spreadable or piping consistency. It should look smooth and have a slightly glossy finish.
If the frosting seems too thick, you can add a little more orange juice to loosen it up. Conversely, if it’s too thin, add more powdered sugar until you reach your desired consistency.
Finally, taste your creation! This is the moment to adjust the flavor if necessary. You can add a bit more orange zest or juice to suit your preference. Once you are satisfied, your Orange Buttercream Frosting is ready to be used!
