Ingredients

For the dough:

• ¾ cup brown sugar

• 2 tbsp molasses 

• ½ cup unsalted butter

• 1 tsp vanilla extract

• 1 egg

• ¾ cup all purpose flour

• 1 ½ cups old fashioned oats

• ¼ tsp baking powder

• 1 tsp salt 

For the filling:

• ½ cup unsalted butter

• 2 tbsp heavy cream

• 2 tbsp eggnog

• 3 cups powdered sugar

• 1 tsp rum extract 

• 1 tsp cinnamon

Instructions

1. Preheat the oven to 350 degrees.

2. In the bowl of an electric mixer, add the butter, molasses, and sugar and cream together on medium speed until light and fluffy, about 2 minutes. Add the egg and beat until combined.

3. In a separate bowl, whisk together the flour, baking powder, and salt.

4. Add the flour mixture to the butter mixture and mix on low speed until almost fully combined. Stir in the oats with a spatula until evenly incorporated.

5. Use your hands to form 20-24 even sized dough balls. Place the balls two inches apart on a large cookie sheet or two smaller ones lined with parchment paper. Bake for 10-12 minutes.

6. Meanwhile, start the filling by beating the butter in an electric mixer on medium speed for about 2 minutes. Add the eggnog and heavy cream and beat for another 2 minutes until smooth. Keep your eye on this mixture because it can seize up quickly.

7. Add the powdered sugar 1 cup at a time, beating on low speed and fully combining between cup. Once incorporated, add the rum extract and cinnamon and beat the filling for an addition 2-3 minutes until fluffy.

8. When the cookies are done, let them cool at room temperature for at least 30 minutes or until they are no longer warm to the touch.

9. Fill a piping bag fitted with a 1 inch tip with the filling. Pipe about 2 tbsp of filling onto half of the cookies in a circular motion. Sandwich each with a corresponding bare cookie, slightly pressing down until the filling fills the the edge.