Preheat the oven to 350°F and line a cupcake tin with liners.
Whisk the flour baking soda powder salt cinnamon and nutmeg in a large bowl and set aside.
In the bowl of your stand mixer or with a hand-held mixer mix the olive oil molasses sugar eggs yolk zest and stout on medium-low until combined.
Reduce the speed to low and add the flour mixture a little at a time until all incorporated.
Divide batter evenly among the prepared pan and bake for about 20 minutes or until a toothpick inserted in the center comes out clean. *If using a mini cake pan grease pan and divide batter evenly filling each about 2/3 full bake for 20 minutes.
Remove from oven and cool on a wire rack 5 minutes before removing from pan to cool completely.
Combine the confectioners’ sugar coconut oil and Irish cream in a bowl and whisk to combine start with less of the cream and add to your taste.