For the rum-coconut madeleines, cream sugar and eggs, add sifted flour, milk and baking powder a little at a time.
Add the warm melted butter, coconut flakes and rum and chill for at least 2 hours.
Pour into madeleine molds (fill only about 3/4 full) and bake the rum-coconut madeleines in the preheated oven at 200 degrees on the bottom rack for about 15 minutes.