For cake:

• Preheat oven to 400 degrees (F).
• Grease a half sheet pan (approx 18×13) and set aside.
• In a medium, heavy-bottomed saucepan over medium heat, melt butter and shortening together.
• Once mostly melted, add water and cocoa powder. Use a wire whisk to stir until smooth. Remove from heat.
• In a large bowl, combine flour and sugar.
• Pour warm chocolate mixture over the flour mixture, and beat on low speed until just combined.
• Add buttermilk, eggs, vanilla and baking soda, and beat until completely combined and smooth.
• Pour into greased sheet pan, and bake for 18-20 minutes.
• Immediately poke holes in the top of the cake and allow to cool slightly while you prepare frosting.

For icing:

• Toast coconut in a dry skillet over medium heat until golden brown, stirring constantly. Set aside.
• In a medium microwave safe bowl, combine butter and milk and bring to a boil.
• Add 1/3 cup caramel sauce and powdered sugar and vanilla and stir until smooth.
• Pour frosting evenly over top of cake.
• Immediately sprinkle with top of warm frosting with toasted coconut.
• Drizzle generously with chocolate and caramel topping.
• Enjoy!