Significantly tastier than notoriously-bland fondant, modeling chocolate is delicious way to adorn cakes and patisserie.
Set a heat-proof bowl over a pan of simmering water; turn off heat. Place chocolate in bowl; stir just until melted. Remove bowl from pan; stir in corn syrup. Transfer dough to plastic wrap; wrap well. Let set at room temperature until firm, preferably overnight.
When ready to use, knead dough until it is pliable and can be rolled out with a small rolling pin. If necessary, heat in a microwave, covered, for 3 to 5 seconds.