01 -
Preheat oven to 175°C. Cream softened butter with both sugars in a stand mixer with paddle attachment on medium-high for 2 to 3 minutes until mixture is fluffy and light in color.
02 -
Scrape down sides of the mixing bowl. Add egg yolk on low speed until combined. Increase to medium-high and beat for 1 to 2 minutes until mixture turns pale and sugars are dissolved.
03 -
On low speed, add flour, oats, baking powder, baking soda, and salt. Mix 60 to 75 seconds until dough just comes together. Scrape down bowl to ensure even mixing.
04 -
Line a quarter sheet pan with parchment paper or silicone mat. Spread dough evenly to 0.6 cm thick. Bake for 15 minutes until golden brown. Cool completely.
05 -
Break cooled oat cookie into pieces and pulse with brown sugar and salt in a food processor until finely crumbed. Transfer to a bowl and knead in melted butter until mixture holds together when pressed. Add extra melted butter if needed.
06 -
Divide crust mixture evenly between two 25 cm pie tins. Press firmly on bottom and sides for even coverage. Use immediately or wrap and store at room temperature up to 5 days or refrigerated for up to 2 weeks.
07 -
Combine granulated sugar, light brown sugar, salt, corn powder, and milk powder in stand mixer bowl. Mix on low speed to evenly combine.
08 -
On low speed, slowly add melted butter until dry ingredients are fully moistened.
09 -
Add heavy cream and vanilla extract; mix until completely incorporated and mixture is smooth. Scrape bowl as needed.
10 -
Add egg yolks and mix just to combine. Avoid overmixing to prevent aeration. Use filling immediately.
11 -
Preheat oven to 175°C. Place pie tins on baking tray. Divide filling evenly between crusts, filling each about three-quarters full. Bake for 15 minutes; centers will be set but very jiggly and tops golden.
12 -
Open oven door and reduce temperature to 160°C. Keep pies in oven while temperature lowers, about 5 to 10 minutes. When oven reaches 160°C, close door and bake an additional 5 minutes. If centers remain too jiggly, bake 5 minutes longer.
13 -
Remove pies from oven; cool on wire rack to room temperature. For best results, refrigerate or freeze pies for at least 3 hours or overnight before serving.
14 -
Dust pies generously with confectioners’ sugar just before serving. Slice and enjoy.