Instructions

CAKE

1. Spray 3 8-inch round cake pans with nonstick baking spray and set aside. Adjust an oven rack to the center position and heat oven to 350 degrees. In a large bowl whisk flour, baking soda, baking powder, cinnamon, ginger, cloves, nutmeg, allspice, cardamom and salt to combine.
2. In the bowl of a stand mixer, combine the pumpkin, sugar and oil on medium-low speed for 2 minutes.
3. Add eggs in one at a time, on low speed beating until just combined. Stir in orange zest.
4. Add the dry ingredients into the wet ingredients and beat on low speed until just combined. Give the batter a final stir by hand with a rubber spatula. Divide cake batter between prepared cake pans and bake for 20 to 26 minutes or until a wooden skewer inserted in the center comes out with a few moist crumbs attached. Let cakes cool in their pan for 10 minutes and then invert on to cooling racks to cool completely.

PUMPKIN BUTTERCREAM

1. In the bowl of a stand mixer fitted with the whisk attachment, pour in the egg whites and sugar and whisk by hand until combined. Fill a medium saucepan with about 2 inches of water and bring to a simmer. Place mixer bowl on top, being sure the bottom of the bowl does not touch the water and attach a candy thermometer.
2. Whisking occasionally, heat the egg mixture until the temperature reaches 160 degrees. Once the mixture reaches 160 degrees, transfer to a stand mixer and beat the mixture on high speed for 10 to 12 minutes or until medium-stiff peaks form. At this point the outside of the mixer bowl should be room temperature. Switch out the whisk attachment with the paddle attachment and with the mixer on low speed, add the butter one tablespoon at a time, and then add the vanilla extract and pumpkin puree. Once combined, turn up the mixer speed to medium-high and beat until the buttercream is smooth about 5 minutes.

ASSEMBLE

1. 
   Trim domes of each cake layer to create 3 even layers of cake. Place one cake layer on a cake platter and spread about 1 cup buttercream on top in an even layer. Place a second cake layer on top and spread the 1 cup buttercream on top in an even layer. Place the last cake layer on top (cut side down) and spread buttercream over the top and sides of the cake. Use a cake comb to add a decorative finish to the sides of the cake. Chill the cake in the refrigerator while you prepare a piping bag.
2. Place remaining buttercream in a piping bag fitted with a piping tip (I used Ateco #808) and set aside.
3. Remove the cake from the refrigerator and decorate the top edges by piping dollops of buttercream around the outside edges. Top each dollop with a marshmallow pumpkin if using and sprinkles.