Preheat the oven to 350 degrees F and line a baking sheet with parchment paper.

In the bowl of a stand up mixer, cream together the butter and sugars until light and fluffy.

Scrape down the sides of the bowl, add in the egg yolk and mix until well combined.

Then add in the flour, oats, salt, baking powder and baking soda.

Cream until well combined (approximately 1 minute).

Put the cookie dough on the baking sheet.  Use a spatula to spread it out until its approximately 1/4” thick (the dough may not cover the entire pan).

Bake for 15 minutes until the edges are set.

Then cool the cookie completely.

Preheat the oven to 350 degrees F and position the rack in the center of the oven.

Put the prepared oat cookie, brown sugar and salt in a food processor.

Pulse until the mixture is all turned into crumbs. (If you don’t have a food processor, you can break the cookie by hand). Move the mixture to a mixing bowl.

Stir in the melted butter and knead it into the cookies with your hands until the mixture can form into a ball.  (If the mixture is not moist enough to mix into a ball, gradually add in more melted butter 1 tbsp at a time until it does.)

Then divide the mixture evenly in between 2 10 inch pie tins.

Use your fingers to press the cookie dough crust into each pie tin.

Make sure to cover the bottom and the sides of the pie tins.

Then place the pie crusts on baking sheets.

In the large bowl of a stand up mixer with a paddle attachment, combine the sugar, brown sugar, milk powder, corn powder and salt on low speed.

Then add in the melted buttered mix for 2-3 minutes until the dry ingredients are moist.

Then add in the heavy whipping cream and vanilla extract.

Mix on low speed until just combined.  Scrape down the sides of the bowl. Then add in the egg yolks.

Mix them into the filling until just combined on low speed.  Be careful not to over mix.

Then divide the filling evenly between the 2 pie crusts (filling the crusts approximately 2/3 of the way full). Bake on the center rack for 15 minutes until the top of the pies are golden brown but still jiggly.

Then open the oven door and reduce the oven temperature 325 degrees F.

Allow the oven to adjust to this new temperature.  Leave the door opened during this time and leave the pies in the oven.

Once the oven reaches 325 degrees F, close the oven door and cook the pie for 5-10 more minutes until the outside edges are set but the center is still jiggly.

Remove the pies from the oven and move them to a wire rack to cool to room temperature.

Then move the pies to the freezer and freeze for 3 hours (or overnight).

Move the pie to the refrigerator for 1 hour prior to serving so that the pie can defrost out slightly.

Dust the top of the pie with confectioner’s sugar right before serving and enjoy!