Preheat the oven to 180°C and line cupcake pan(s) with cupcake papers.
In a mixing bowl, beat eggs, butter and sugar until light and fluffy.
Add milk, flour and vanilla to the mixing bowl and beat with an electric mixer until combined and smooth in consistency.
Using an ice-cream scoop, scoop the batter into the lined cupcake pan(s) and bake for 20 minutes (depending on your oven, baking time may vary).
Making the buttercream:
Beat the butter until creamy.
Add the icing sugar, milk, vanilla essence and pink food dye (a drop at a time, depending on the shade of pink you desire) and beat until combined; creamy and smooth.
If buttercream is too dry, add one tablespoon of milk (or more if required). To thicken buttercream, add more icing sugar.
Scoop the buttercream into a piping bag or a zip-lock bag fitted with WIlton's 1M nozzle.
Starting from the center of the cupcake, with medium pressure, squeeze the piping bag to create a star and without releasing any pressure, pipe all around the cupcake until it covers the edge of the cupcake.Then release pressure as you pull the piping bag away from cupcake to complete the rose swirl.