Preheat the oven to 350º F and lightly grease a jelly roll baking sheet with butter or non-stick spray.
In a medium bowl, whisk together the flour, baking soda, and salt, then set aside.
In a large bowl or mixer, cream together the butter and sugar for 4-5 minutes, or until fluffy and lightened in color.
Add the eggs and beat until fully incorporated, then mix in the vanilla extract.
Beginning and ending with the dry ingredients, alternate between adding the flour mixture and buttermilk mixture to the cake mix, mixing until just incorporated.
Fold in the shredded coconut and chopped pecans, then pour the batter into the greased baking sheet.
Place in the oven and bake for 17-20 minutes, or until a toothpick inserted in the center comes out mostly clean. Remove from the oven and let cool.
To make the icing, cream the butter and cream cheese together in a large bowl or mixer for 3-4 minutes, or until fluffy.
