A nostalgic treat made up of two chewy, buttery oatmeal cookies sandwiching a sweet, rich and creamy filling. A childhood favorite that's a hundred times better than store bought!
Preheat oven to 350 degrees. Line 18 by 13-inch baking sheets with parchment paper.
In a mixing bowl whisk together oats, flour, baking soda, salt, cinnamon, nutmeg and ginger (if using) for 30 seconds. Set aside.
In a large mixing bowl using an electric hand mixer (or in stand mixer fitted with the paddle attachment) cream together 1 cup butter, the granulated sugar and brown sugar for a few minutes until slightly pale and fluffy.
Blend in molasses, scrape down bowl. Mix in egg, then blend in egg yolk and vanilla extract, scrape down bowl.
Pour in flour mixture and mix until combined. Scrape bowl and fold batter a few times to ensure everything is evenly incorporated.
Scoop dough out 1 1/2 Tbsp at a time (using a #40 scoop works well, if you don't use a scoop then shape into balls). Drop 12 spaced evenly apart onto parchment lined baking sheets and flatten slightly.
Bake one sheet at a time until cookies are setting on edges but slightly under-baked in center, about 9 minutes.
Let cool on baking sheet for a few minutes then transfer to a wire rack to cool completely. Repeat baking process with remaining cookies.
For the Cream Filling
In a mixing bowl using an electric hand mixer (or use an electric stand mixer), cream together 8 Tbsp unsalted butter and cream cheese until blended and smooth.
Add powdered sugar and vanilla extract and whip on high speed for about 2 to 3 minutes until light and fluffy.
Spread or pipe filling between two sandwiches cookies each. Store cookies an airtight container in the fridge once filling is added and bring to room temperature before serving.