Add the butter to a stand mixer (or electric mixer) and beat until light and creamy. This should take a few minutes. Gradually add the confectioners' sugar, one cup at a time. Once combined, add the extracts, salt, and milk. Keep mixing until you reach the consistency you're looking for.
Place the buttercream into the refrigerator covered in plastic wrap, for at least one hour. When ready to use, line a sheet with parchment paper.
Using a tablespoon, scoop the buttercream into small balls and place it on your prepared baking sheet. Do this until all buttercream has been used. Place in the fridge again, for at least an hour.
Add baking chocolate to a heat-safe bowl and melt in the microwave. Do this in 20-second intervals, checking often. Do this until the chocolate is melted and then leave it to cool.
Place the buttercream balls into the cooled melted chocolate; ensuring full coverage. Lift out the buttercream ball and place it onto a baking sheet. Repeat until all balls are coated and pour any leftover chocolate over the balls. Chill until the chocolate is set. Enjoy!