In a bowl, dissolve gelatin in 1 cup milk. In a small saucepan over medium-high heat, combine drink mix, sugar and remaining milk; bring to a boil, stirring until chocolate and sugar are dissolved. Add to gelatin mixture and mix well. Pour into an 8-in. square pan. Cool at room temperature for 30 minutes. Cover and refrigerate until firm, about 5 hours. (do not freeze). Cut with a knife or cookie cutter.