After one bite, you will understand how this sweet and salty pie got its name. Be sure to save some for your family or guests.
Oat Cookie Crust:
non-stick cooking spray
9 T. unsalted butter, room temperature, divided
5 1/2 T. packed golden brown sugar, divided
2 T. sugar
1 large egg
3/4 c. & 2 T. old-fashioned oats
1/2 c. all-purpose flour
1/8 t. baking powder
1/8 t. baking soda
1/4 t. salt
Filling:
3/4 c. sugar
1/2 c. packed golden brown sugar
1 T. non-fat dry milk powder
1/4 t. salt
1/2 c. (1 stick) unsalted butter, melted, cooled slightly
6 1/2 T. heavy whipping cream
4 large egg yolks
1 t. vanilla extract
powdered sugar, for dusting
Oat Cookie Crust:
Preheat oven to 350 degrees. Line a 13 x 9x 2 inch metal baking pan with parchment paper, then coat with non-stick spray.
Combine 6 T. butter, 4 T. brown sugar, and 2 T. sugar in medium bowl. Using an electric mixer, beat mixture until light and fluffy, occasionally scraping down sides of the bowl, about 2 minutes. Add egg and beat until pale and fluffy. Add oats, flour, baking powder, baking soda, and salt; beat until well blended, about 1 minute. Turn oat mixture out onto prepared baking pan; press out evenly to edges of pan. Bake until light golden on top, 17 - 18 minutes. Transfer baking pan to rack; cool cookie completely.
Using hands, crumble oat cookie into a large bowl; add 3 T. butter and 1 1/2 T. brown sugar. Rub in with fingertips until mixture is moist enough to stick together. Transfer cookie crust mixture to 9 inch diameter glass pie dish. Using fingers, press mixture evenly onto bottom and up sides of pie dish. Place pie dish with crust on rimmed baking sheet.
Filling:
Position rack in center of oven; preheat to 350 degrees.
Whisk both sugars, milk powder, and salt in medium bowl to blend. Add melted butter; whisk until blended. Add cream, then egg yolks and vanilla; whisk until well blended. Pour filling into crust. Bake pie 30 minutes (filling may begin to bubble). Reduce oven temperature to 325 degrees. Continue to bake pie until filling is brown in spots and set around edges but center still moves slightly when pie dish is gently shaken, about 20 minutes longer.
Cool pie 2 hours in pie dish on rack. Chill uncovered overnight.
Sift powdered sugar lightly over top of pie. Cut pie into wedges and serve cold.
**Do Ahead: Pie can be made 2 days ahead of time. Cover; keep chilled.