If you buy ready-made royal icing, or if you make your own, peppermint creams are easy, and you can easily half-dip them in chocolate to make them look really professional. get a stiff icing mixture, add a few drops of oil of peppermint ( Not the same as peppermint essence - essence will soften the mix too much )
Knead well, divide mass into two, add green colour to one, knead. Roll out the icing mixture, between sheets of bakewell paper or polythene, and cut circles - I use the top of a little pot of spice. When the circles have dried in the airing cupboard overnight ( on trays lined with greaseproof) melt some chocolate gently in the microwave and half-dip each sweet. Lay them back on the same trays for the choc to set.