Bake until a toothpick inserted in center comes out clean, 1-1/4 to 1-1/2 hours. Cool in pan 10 minutes before removing to a wire rack to cool completely. For frosting, in a large bowl, beat cream cheese, butter, lime zest and lime juice until smooth. Gradually beat in confectioners’ sugar. Spread over cake. If desired, garnish with lime slices and additional zest.