In a small mixing bowl, break apart and place the chocolate, if required (only if you use bar chocolate vs chips)

Quarter the softened butter and place over top of the chocolate in the mixing bowl.

In a small sauce pan, over low-medium heat, slowly heat the heavy cream (and the brown sugar if you intend to sweeten the ganache) until it begins to steam and sugar has completely dissolved (be sure to stir regularly to avoid scorching) and then pour the hot cream over the chocolate and butter.

Let the hot cream and other ingredients sit for about five minutes to allow the hot liquid to melt the chocolate and butter, then stir until fully combined. Give it another five minutes to cool to about room temperature before using.