Melt 1/4 cup of the butter over low heat in skillet, add rum and brown sugar make sure evenly coats bottom.
Arrange raspberries in an even layer over brown sugar/rum mixture. Let cook for 5 minutes before removing from heat. Coat with coconut.
In a large bowl, cream other 1/4 cup of butter with the sugar. Add eggs, one at a time, mix until blended. Add milk, and vanilla. Beat until sugar is well dissolved.
Sift flour, cocoa, baking powder and salt and mix with the egg mixture until well blended.
Pour batter into the skillet/pan.
Bake at 350 degrees for 35 minutes.
Let cool for 10 minutes and then put plate over skillet/pan and flip over.