Prepare brownie mix according to package directions in a greased 9-onch round pan; cool. In a mixing bowl, dissolve coffee powder in water; add cream cheese. With electric mixer, beat mixture until smooth; blend in marshmallow creme. Melt Junior Mints -place in a microwave-safe bowl and heat on HIGH for 1 1/2 to 2 minutes, stir until smooth; OR place in a small saucepan and stir over low heat. Stir in melted Junior Mints (the chocolate will form slivers in the mixture). Fold in whipped cream and spread onto brownie. Loosely cover and chill several hours or overnight. To serve, cut into wedges and garnish as desired.