For the cake:

1. Preheat oven to 350 degrees F.
2. In a medium sized bowl, mix together dry ingredients (flour, salt, nutmeg, cinnamon, baking powder). Set aside.
3. In a stand mixer, paddle sugar into butter on medium-high for 2-3 minutes or until a creamy consistency. Then add in eggs while mixing over low.
4. Add in 1/3 of dry mixture. Then add oil and rum extract. Then add another 1/3 of dry mixture. Now add eggnog and milk, following with the rest of the flour mixture. Scrap the sides down and give the mixture a final mix with a rubber spatula.
5. Pour into 1/2 sheet tray (18×13) lined with silicone baking mat or parchment paper.
6. Bake the cake for about 30 minutes; when you poke the edge of the cake with a finger, the cake should bounce back slightly and the center should no longer be jiggly.
7. Allow the cake to cool completley.

Mixing Frosting:

Assembling the cake:

1. Put a piece of parchment or Silpat on the counter. Invert the cake onto it, pull away your sheet pan, and peel off the parchment or baking mat from the bottom of the cake. Use the cake ring to stamp out 2 circles from the cake. These are your top 2 cake layers. The remaining cake “scrap” will come together to make the bottom layer of the cake
2. Layer 1, The Bottom: Clean the cake ring and place it onto a cardboard cake round (at least 8 inches). Use 1 strip of acetate to line the inside of the cake ring. Put the cake scraps in the ring and use the back of your hand to smash the scraps together into a flat even layer .In a small bowl, pour in the eggnog. Using a pastry brush, brush half of the eggnog over the top of the cake. Using a piping bag, spread one-fifth of the frosting in a circular swirl over the cake layer. Smooth with an offset spatula. Sprinkle extra cake crumbs in an even layer over the frosting, then cover the crumbs with another layer of frosting.
3. Layer 2, The Middle: With your index finger, gently tuck the second strip of acetate between the cake ring and the top 1/4 inch of the first strip of acetate, so that you have a clear ring of acetate 5 to 6 inches tall. Set one of the cake rounds (the more imperfect of the two) on top of the frosting, brush with the remaining soak, and repeat the process for Layer 1 (a fifth of frosting, a third of crumbs, and another fifth of frosting).
4. Layer 3, The Top: Nestle the remaining cake cut out round into the frosting. Cover the top of the cake with the last fifth of the frosting. Spread remaining frosting on the sides of the cake, smooth with a bench scraper.
5. Transfer to the freezer and freeze overnight. Pull the cake out of the freezer. Peel the acetate off gently. Pull the cake ring up and off. Transfer to a cake stand let it defrost for a minimum of 3 hours before serving.