2 sticks butter, at room temperature
2 cups dark brown sugar, firmly packed
2 tablespoons milk
2 teaspoons vanilla extract
3 cups all-purpose flour
2 teaspoons kosher salt
4 teaspoons baking powder
1/2 teaspoon baking soda
3 cups oatmeal
4 sticks butter, at room temperature
3 cups powdered sugar
1/2 teaspoon kosher salt
1 teaspoon lemon juice
1 teaspoon vanilla extract
How to Make It
FOR THE COOKIES: Allow all ingredients to come up to room temperature before beginning. Preheat the oven to 350˚. In a mixer with a paddle attachment, cream the butter and sugar together until light and fluffy about 5 minutes. Scrape down the bowl, making sure to get the bottom of the bowl and the paddle. On medium speed, add in the eggs one at time and mix for another 2 minutes.
In a separate bowl, whisk together the flour, salt, baking powder and baking soda to combine. On low speed add half of the flour mixture until just combined. Then add in the milk and vanilla extract, scrape then add the rest of the flour mixture.
Mix in the oatmeal until just incorporated, give it one more scrape and portion with 2-ounce scoops onto a greased cookie sheet. Chill the sheet for 30 minutes before baking to ensure proper spreading during the bake. After the chill, bake cookies for 10-13 minutes, until the outside of the cookies are golden brown. Let cookies cool before assembling cream pies.
FOR THE BUTTERCREAM: On lowest speed, combine all ingredients in a mixer with the whip attachment. Scrape down the bowl making sure to get the bottom of the bowl and the whip. Once the sugar is incorporated, turn speed up to medium-high and whip for 6 minutes or until the icing is fluffy and shiny.
TO ASSEMBLE: Once the cookies are cool, use a 2-ounce scoop of icing between 2 cookies. Serve immediately or they will hold wrapped tightly in the refrigerator for 3 days or in the freezer for 2 weeks.