In a large mixing bowl, beat together salted butter and a mix of light brown and granulated sugar until creamy, about 2-3 minutes. Add egg, egg yolk, and vanilla extract.

In a separate bowl, whisk together all-purpose flour, cornstarch, baking soda, and kosher salt. Gradually incorporate into the wet mixture.

Divide the dough into three portions and line the bottom of the 8-inch pan with parchment paper. Press one third of the dough into the bottom for the crust.

Melt peanut butter slightly and spread it evenly over the crust. Layer with mini Reese's Peanut Butter Cups and freeze for 10-15 minutes.

Soften Nutella slightly and spread it over the peanut butter layer, then sprinkle white chocolate chips and freeze for another 10 minutes.

Spread marshmallow cream over the Nutella layer and top with mini Toblerone pieces.

Use the remaining dough to cover the layers, sealing the edges. Freeze the pie for another hour.

Preheat oven to 350°F. Bake for 30 minutes until lightly golden and edges begin to crack.

Let cool for 15-20 minutes, then refrigerate overnight for the best texture and flavor.

Slice and serve topped with mini Reese's, melted dark chocolate, and Butterfinger pieces.