Place chocolate in a 1-quart heatproof container about 5 inches deep and at least 6 inches in diameter. Melt chocolate gently in a barely simmering water bath, stirring frequently until melted and smooth, about 120° for dark chocolate and 110° for white or milk chocolate. Or, melt in the microwave on medium (50%), stirring once or twice, for about 5 minutes for dark choc