Preheat your oven to 350°F (175°C) and prepare two 9-inch round cake pans by greasing and lining with parchment paper.

In a large bowl, whisk together all-purpose flour, baking powder, baking soda, salt, cinnamon, ginger, and nutmeg. Set aside.

In another bowl, beat together granulated sugar, brown sugar, and softened butter until light and fluffy, about 3-5 minutes.

Add eggs one at a time, mixing well after each. Then blend in vanilla extract until smooth.

Gradually add the dry mixture to the wet mixture, alternating with buttermilk until just combined.

Divide the batter between the prepared pans and bake for 25-30 minutes until a toothpick comes out clean.

Let the cakes cool in the pans for about 10 minutes, then transfer to wire racks to cool completely.

For the buttercream, beat softened butter until creamy, then gradually add powdered sugar, eggnog, and cream, mixing until fluffy.

Frost the top of one cake layer with buttercream, add the second layer, and frost the top and sides of the cake.

Garnish with a sprinkle of nutmeg or cinnamon before serving.