Once the water has reached a boil, place the chopped chocolate and butter into the heat safe bowl. Over medium high heat, allow the chocolate and butter begin to melt. Once each has started melting, stir to ensure even melting.
Pour in the brownie batter into the prepared pan. Smooth the batter into the corners and across the top. Bake the brownies at 350F for 25-35 minutes. The edges should be set and slightly pulling away from the edges of the pan. The center will be barely set.