Preheat oven to 350°. In small saucepan over low heat, combine 1 cup milk chocolate morsels and butter; stir until morsels are melted and mixture is smooth. Cool to room temperature. In large bowl, combine sugar and eggs; beat until thick and lemon colored. Gradually beat in chocolate mixture and vanilla extract. In cup, combine Irish whiskey and instant coffee; stir until dissolved. Add to chocolate mixture. Gradually blend in flour. Pour into foil-lined 8-inch square baking pan. Bake at 350° 25 to 30 minutes. Immediately sprinkle remaining 1 cup milk chocolate morsels on top. Let stand until morsels are shiny and soft; spread evenly. Cool completely on wire rack; cut into 2-inch squares.