Preheat the oven to 350°F, and line two baking sheets with parchment paper.
Sift all the dry ingredients, and set aside.
2 cups All-purpose flour, ¼ teaspoon Salt, 2 teaspoon Baking powder, 1 teaspoon Nutmeg, 1 teaspoon Cinnamon, ¼ teaspoon Clove
Start beating the foftened butter with two sugars for a good 5 minutes until light and fluffy.
¾ cup Butter, ½ cup Granulated sugar, ½ cup Light brown sugar
Add in the yolks, vanilla extract, and rum and mix well.
1 teaspoon Vanilla extract, 1 tablespoon Rum, 2 Egg yolks
Next, add the eggnog and mix. Switch to a rubber spatula and gently fold in the dry ingredients just until there is no trace of flour is seen.
½ cup Eggnog
Using an ice cream scoop make small balls of dough, the size of a large walnut. Place them on the lined baking sheets. Leave at least 2 inch of space between them.
Bake them for 10-12 minutes or until the edges are slightly golden. Let them cool down on the baking sheet for 10 minutes, then transfer to a cooling rack to cool down compeletly.
For the topping, melt half a cup of milk chocolate, and using a small spoon drizzle it over the cool cokies.