Melt the white chocolate over a bain marie, stirring until smooth, then let it cool.

Beat the softened butter on low speed until creamy, then gradually add the icing sugar, mixing until fully combined.

Once the white chocolate is cooled, add it to the butter and sugar mixture and mix until smooth.

If the buttercream is too thick, add a little milk, one teaspoon at a time, mixing until you reach the desired consistency.

Your delicious White Chocolate Buttercream Frosting is now ready to use!