Preheat oven to 350°F. Line 2 baking sheets with parchment paper. Set aside.
To Prepare Cookie Dough: In a medium size mixing bowl, use a whisk to sift together flour, baking powder, salt, ground cinnamon, nutmeg and allspice.
Using an electric mixer in a large bowl cream together butter, brown sugar, and granulated sugar on medium-high speed until light and fluffy. Add vanilla extract, and almond extract, whole egg plus egg yolk, and eggnog. Beat on medium-low speed until fully combined.
Gradually add dry ingredients to the creamed mixture. Stop and scrape the sides of the bowl periodically.
Using a medium cookie scoop divide the cookie dough into approximately 1 1/2 tablespoons of batter. Drop on the prepared pan at least 2 inches apart.
Bake for 12-14 minutes or until lightly golden on the edges. Leave to cool on the cookie sheet for 5 minutes then transfer to a cooling rack to cool completely.
To Prepare the Glaze: In a small bowl, whisk together powdered sugar, eggnog, vanilla and salt until smooth. (It will be slightly runny). Dip or drizzle cooled cookies while on cooling rack. Dust tops with additional cinnamon or nutmeg after glazing, if desired.
Allow cookies to stand until glaze is set then enjoy with milk, warm cider, hot tea or coffee!