In a heatproof bowl, combine the butter and chopped chocolate, and set over a saucepan filled with a few inches of simmering water over low heat. Let melt, 3 to 4 minutes, then stir until smooth.
And Ree Drummond (a.k.a. The Pioneer Woman) says her Brown Sugar Oatmeal Cookies are just that. They're made with melty brown ...