1stick, 8 tablespoons unsalted butter, room temperature
1cuppacked brown sugar
1egg, room temperature
1teaspoonvanilla extract
1/2cupsour cream, room temperature
1/3cupmolasses
1/4cupvegetable oil
Eggnog Filling:
1stick, 8 tablespoons unsalted butter, room temperature
8tablespoonsvegetable shortening
1cupmarshmallow creme
1tablespoondark rum
3/4teaspoonground nutmeg
1 1/2cupssifted powered sugar
Instructions
Position a rack in the center of the oven and preheat to 350°. Line two baking sheets with parchment paper.
In a medium bowl, whisk together the flour, ginger, cinnamon, baking soda, salt, and nutmeg;set aside.
In the bowl of a stand mixer fitted with the paddle attachment, beat together the butter and brown sugar on low speed until just combined. Increase the speed to medium and beat until fluffy and smooth, about 3 minutes.
Add the egg and vanilla and beat until combined.
In a two-cup measuring cup with a pour spout, whisk together sour cream, molasses, and oil.
Alternately mix the flour mixture and sour cream mixture to the batter and beat on low until incorporated, starting and ending with the flour mixture.
Drop by tablespoons of batter onto the prepared baking sheets at least 2 inches apart.
Bake one sheet at a time for about 10 minutes each, or until the rounds spring back when pressed gently. Remove from the oven and let the cakes cool on the baking sheet for 5 minutes before transferring them to a rack to cool completely.
To make the filling: In the bowl of a stand mixer fitted with the paddle attachment, beat together butter and shortening on medium speed until combined. Beat in marshmallow creme until combined. Beat in rum, nutmeg, and powered sugar on medium speed until the mixture is smooth and fluffy, about 3 minutes.
Add the confectioners’ sugar and the vanilla and beat on low until incorporated. Increase mixer speed to medium and beat until fluffy, about 3 minutes more.
Pipe filling through a decorating bag onto the flat side of a cooled cake. Top with another cake, flat side down. Repeat with the remaining cakes and serve.