Step 1: Blind Bake the Crust
Preheat your oven to 400°F. Roll out your crust and transfer it to a 9-inch pie plate. Crimp the edges and prick the bottom with a fork. Line the crust with parchment paper and fill with weights. Bake for 15 minutes, remove the weights and paper, then bake for another 15 minutes until the crust is golden brown.

Step 2: Prepare the Filling
In a saucepan over medium heat, combine the peanut butter chips, sweetened condensed milk, and 3 tablespoons of salted butter. Stir constantly until melted. Once smooth, stir in the miniature marshmallows until they are fully incorporated and the mixture is gooey.

Step 3: Assemble the Base
Pour the creamy peanut butter mixture into your pre-baked crust and spread it evenly. Immediately sprinkle the peanuts over the top so they adhere to the warm filling.

Step 4: Make the Caramel Topping
In a small saucepan, melt the granulated sugar over medium heat, stirring constantly until it turns a deep amber color. Stir in the butter cubes until melted, then add the heavy cream. Let the mixture boil for exactly 1 minute.

Step 5: Final Touch
Remove the caramel from the heat and stir in the vanilla and salt. Let it cool for 5 minutes, then drizzle it evenly over the peanuts.

Step 6: Set
Refrigerate the pie for at least 4 hours before slicing. This is essential for the filling to firm up properly.