Preheat the oven to 350 degrees.

In a medium-sized mixing bowl combine the flour, baking soda, oats, cinnamon, nutmeg, and ginger.

In a large mixing bowl beat together 1 cup of butter with the granulated sugar and the brown sugar. 

To the sugar mixture add the eggs, 1 tbsp vanilla, and molasses.

Add the dry ingredients to the sugar mixture and beat together until fully combined.

Spray your muffin tin(s) with non-stick cooking spray.

Roll the dough into ~36 balls and place in the muffin tin. The dough should be wet and sticky.

Bake for approximately 10 minutes. The outside of the cookie cups should be fully cooked with the middle slightly undercooked.

Once removed from the oven create a well in the center of each cookie cup.  Then continue to let the cups cool in the muffin tin.

Now make the filling by beating together the remaining butter and powdered sugar.

Add the remaining vanilla to the filling mixture.

Then start by adding 2 tablespoons of heavy whipping cream to the filling mixture.  Add additional tablespoons (one at a time) if you need to thin the filling mixture. 

Once the cups have cooled pop each out of the muffin pan and place on a cooling rack.

At this time you can either pipe or spoon the filling into each cookie cup well. Enjoy!