Roll dough into 1 inch balls and place balls 2 inches apart on baking sheets lined with a Silpat baking mat or parchment paper. Make an indentation in the center of each cookie using your thumb or index finger.
Bake for 12 minutes in preheated oven. Remove from oven and allow cookies to cool on the baking sheet for about 3 minutes then transfer a rack to cool completely.
You can substitute rum extract for the Captain Morgan Spiced Rum. Start by adding 1/2 teaspoon, taste the icing and add additional, if needed.