Alternative method 1

Melt the chocolate in a bowl, then set it in a bowl of cold (not ice) water. Stir the chocolate often until it cools to 80°F/25°C, then set it again above hot water and heat to 88-90°F/30-32°C for bittersweet or semisweet chocolate, or 84-85°F/29°C for milk or white chocolate.