Add food coloring until you reach the desired shade. For the marbling technique, use a toothpick or fork to make swirl designs in the chocolate candy coating. Keep ganache balls refigerated until ready to coat because as the chocolate softens, it makes it easy to start melting when mixed with the white chocolate coating and your white coating will start turning brown. If the mixture starts turning brown, refrigerate the ganache for 10 minutes. Then try stirring and reheating the ganache for 20 seconds.