For the cake:
Preheat the oven to 180°C and grease and flour one 9-by-12-by-2-inch cake pan.
In a large mixing bowl, mix the gelatin, granulated sugar, flour, salt, baking powder and baking soda. Stir to mix well. Add the oil, orange juice, lemon juice, vanilla, and eggs. Mix until well combined. Pour the batter evenly in the pan and bake for 35 to 40 minutes. Test for doneness by lightly touching the tops or inserting a toothpick. Cool the cake in the pan for 5 minutes then turn out onto a cooling rack.
For the glaze:
While the cake is still hot, mix the lime juice and confectioners' sugar together well. Pierce the cake with a fork to allow the glaze to soak in better and pour it over the cake on the cooling rack. Allow cake to cool completely as you prepare the icing.
For the icing:
Cream the butter and cream cheese. Beat in the confectioners' sugar until mixture is smooth and easy to spread. Spread the icing on the top and sides of the cake.
Cook's Note: you can also use three 9-inch round cake pans and make this into a layer cake.
Recipe adapted from Home Cooking with Trisha Yearwood (c) Clarkson Potter 2010