Sift together the flour, salt, and cocoa powder in a bowl and set aside.

In a separate bowl, cream together the butter and sugar using electric beaters, until slightly whipped but not overworked.

In another bowl, mix the egg, milk, and vanilla extract.

Now gradually add the wet and dry ingredients to the butter mixture, alternating between the egg-milk mixture and the flour mixture, in two stages, mixing just until all ingredients are incorporated.

Place cupcake liners in a cupcake tray.
Transfer the batter to a piping bag and fill each liner up to ¾ full.
Place a chocolate egg in the center of each cupcake, then cover with a bit more batter to hide the egg.

Bake in a preheated static oven at 180°C for 25 minutes.
Once baked, let them cool completely.

Using electric beaters, whip the soft butter with the powdered sugar and vanilla extract until light and fluffy.
Transfer the buttercream to a piping bag and frost the cooled cupcakes.

Finish by topping with chocolate shavings and colorful chocolate eggs.

By @Frollemente