ATK Oatmeal Cream Pie cookies

This recipe is based on this one from America's Test Kitchen... which does a pretty good job of replicating the flavors and textures of Little Debbie's Oatmeal Cream Pies. (Subscription may be required to ATK.)

Original ATK recipe makes 12 enormous sandwich cookies! We used roughly 2-1/4 tsp of dough for each cookie and maybe came out with 18 manageable sandwich cookies. (We didn't think to count.)

Another note from ATK: The cookies will seem underdone when you pull them from the oven. This is OK; they will continue to bake as they cool on the baking sheet for 5 minutes. This method ensures that the cookies remain chewy once they have cooled.

Many comments on the original recipe include a caution about the cookies being too thick, so we suggest gently pressing the dough until it is about 1/8" high.

We found the filling to be a tad sweeet, so perhaps reduce the amount of confectioner's sugar.

Comments also recommend adding xantham gum to the marshmallow filling so it won't be so runny, though we also found that keeping the cookies in the fridge does the trick, and these were delicious right from the fridge or even freezer.

INGREDIENTS

For the cookies   

1 cup (5 ounces) all-purpose flour
1 tsp table salt
3/4 tsp baking soda
3 cups (9 oz) old-fashioned rolled oats
1/2 cup (3 oz) raisins
3/4 cup packed (5-1/4 oz) dark brown sugar
1/2 cup (3-1/2 oz) granulated sugar
1/2 cup vegetable oil
4 Tbl unsalted butter, melted 2 tsp molasses
1/4 tsp ground cinnamon
1 large egg and 1 large yolk
1 tsp vanilla extract

For the filling, which can be made while the cookies are cooling

5 oz (1-1/4 cups) Fluff brand marshmallow crème
no more than 3/4 cup (3 ounces) confectioners' sugar
6 Tbl unsalted butter, softened
1/2 tsp vanilla extract
1/4 tsp table salt
(optional: maybe 1/4 tsp (?) xantham gum, to stiffen the marshmallow filling)

PREPARATION

For the cookies

1. Oven rack to middle position; heat oven to 400 degrees. Line 2 or 3 rimmed baking sheets with parchment paper.

2. In a medium bowl, whisk flour, salt, and baking soda together; set aside.

3. Melt the butter; process oats and raisins in food processor until very finely ground, about 1 minute; set aside in a bowl and wipe out the food processor bowl, reserving it for making the filling.

4. In a large bowl, whisk brown sugar, granulated sugar, oil, melted butter, molasses, and cinnamon until smooth.

5. Whisk in egg, yolk, and vanilla until combined and smoother than before whisking.

6. Use a wooden spoon or spatula to stir in flour mixture until evenly combined and no dry flour remains.

7. Stir in oat-raisin mixture until evenly distributed. Mixture will be stiff.

8. Spoon 2 or 2-1/4 tsp balls of dough and drop them onto one of the parchment-lined baking sheets, evenly spacing the dough balls, 12 balls per sheet. Then dip your fingertips or the bottom of a glass into a small dish of water and flatten the balls to 1/8" thin. (The cookie dough will puff up quite high when baking and should sink back while cooling.)

9. Bake cookies, 1 sheet at a time, until tops are beginning to show small cracks and tops are slightly firm, 5 to 7 minutes. NOTE: They may seem not quite brown enough, but they burn easily and will continue to bake or cure after they come out of the oven.

10. Let cookies cool on sheet for a couple minutes before transfering parchment of cookies to a cooling rack and let cool completely, about 45 minutes, before creating sandwiches. (NOTE: individual cookies freeze well)

For the filling

1. Process all filling ingredients in now-empty and reserved food processor bowl until smooth and fluffy, about 30 seconds, scraping down sides of bowl as needed.

2. Transfer to bowl and stir to incorporate any dry sugar that may have accumlated at the bottom or sides of the bowl.

3. Place a scant tablespoon of the filling on the flat side of a cookie and press with a second cookie on top to make the sandwich. Refridgerate or freeze the assembled cookies until ready to serve.