In large heavy saucepan, combine the butter, cocoa, sugar and coffee. Cook and stir over medium-low heat until melted. Whisk a small amount of hot mixture into egg. Return all to the pan, whisking constantly. Cook and stir over medium-low heat until mixture reaches 160°. Remove from the heat., Stir in the cracker crumbs, coconut and pecans. Press into a foil-lined 8-in. square baking pan. Refrigerate for 30 minutes or until set., For filling, in a large bowl, beat the butter, whipping cream, rum and vanilla until blended. Gradually beat in confectioners' sugar until smooth; spread over crust., In a microwave, melt chocolate chips and butter; stir until smooth. Spread over top. Refrigerate until set. Cut into bars and dust with cocoa.