In a large bowl, place the brown sugar, cocoa powder, baking soda, and salt, and whisk to combine well, breaking up any lumps in the brown sugar. (glutenfreeonashoestring.com)
Mix until incorporated while trying to break up any lumps as much as possible. (confettiandbliss.com)
Add the beef, stirring and breaking up any lumps until it is no longer pink, about 10 minutes. (ahintofhoney.com)