Make sure that your cupcakes are completely cool before you begin the decorating process.
Line a pan with wax paper and fold your two fondant colors with one another. You will want to knead it so that the two colors become marbled and not mix completely.
Grab small pieces of the fondant and shape them into mini eggs, approximately half an inch in size. Place gently on your lined pan.
Using an electric mixer, beat butter, sugar, milk, vanilla extract on in a mixing bowl on medium speed, gradually increasing it to high speed.
Once it's smooth and forms semi-stiff peaks, it's ready. Add your green food coloring and mix until buttercream is completely tinted.
Using Wilton tip #233, frost each cupcake so that it looks like grass by squeezing out some frosting and then pulling immediately when your “grass” is at the right length.
Top with your fondant eggs and serve.