Brown sugar, a combination of regular granulated white sugar and molasses, can add more flavor to your recipes than white sugar alone. It is naturally more moist than white sugar thanks to its molasses content. Melting brown sugar on the stove can be difficult unless you are adding liquid ingredients (such as butter or water) that can partially dissolve the sugar. If you attempt to melt brown sugar alone on the stove, you are just as likely to end up with scorched brown sugar. This would be fine if you were shooting for brown sugar caramel, but not ideal if you simply want melted brown sugar.
Place the brown sugar into one microwave-safe bowl. Fill the other bowl partially with water. This water will help keep the brown sugar moist and is especially important if your brown sugar has begun to harden or dry out.
Microwave the bowls of sugar and water for 30 seconds on high. Remove the bowl of brown sugar from the microwave and stir it gently. It should be noticeably softening at this point. Return the brown sugar to the microwave and microwave it for another 30 seconds, and then remove and stir it again.
Continue microwaving the sugar in 30-second intervals, stirring it between each time, until it is melted to your satisfaction.