I decorated the macarons by airbrushing their surface, after the macarons had baked and cooled down completely.
When you are airbrushing shells, make sure to not soak them with food coloring, lightly brush them in the lowest possible setting of your airbrushing pen, very quickly.
After the spray has cooled down, you can drizzle melted white chocolate over the macarons.
Now about the delicious filling. This white chocolate macaron filling is super easy to make. By adding melted white chocolate to a simple American buttercream, you can totally elevate not only the texture but also the taste of the frosting.
This Condensed Milk Chocolate Frosting is also known as Russian Buttercream.