Method:
For the Pie Dough: Combine flour, cocoa, sugar and salt in a food processor and pulse them 4-5 times to blend. Add butter and pulse 2-3 times to blend, until mixture looks sandy. Strain ice water into food processor and run processor for 5-10 seconds to bring mixture together. If it seems a little dry, add more ice water 1 tablespoon at a time. The dough will resemble small pebbles and hold together when you squeeze a bit in your hand.

Turn dough out onto a floured counter into a pile. Sprinkle the top lightly with flour. Starting at one end, use the heel of your hand to smear a small amount of dough against counter and continue moving through the pile until you have smeared most of it into flakes of dough. Do this quickly, being sure not to work any section of dough more than once. Once all the dough has been flattened, pile the layers up into a stack and gently press into a flattened disc.

Lightly flour countertop and roll dough out to fit into a 9-inch deep-dish pie pan. Lay dough in buttered pie pan and gently press it into pan. Trim top edges to 1-inch past edge of pie dish. Fold edge under and crimp circumference of dough. Let pie dough rest in freezer while oven preheats.

Adjust oven rack to centre position and preheat oven to 180°C. Line pie dough with foil or crumpled parchment paper and fill with pie weights. Bake for 20 minutes. Remove pie weights and return pie dough to oven for 10 minutes more. Pie crust should be fully cooked through and just set. Let cool completely at room temperature.

For the White Chocolate Peanut Butter: Put white chocolate, peanut butter, and vanilla paste into a food processor. Pulse machine 5 times to begin blending ingredients. Once a rough paste forms, turn food processor on and let run for 5 minutes until white chocolate and peanut butter form a smooth, uniform paste. Turn food processor off and add salted, roasted peanuts. Pulse machine 10 times to roughly chop peanuts into white chocolate peanut butter mixture. Put mixture into a plastic container, cover and freeze.

When white chocolate peanut butter is frozen, divide it in half. Reserve half in a covered container in refrigerator or freezer. Chop remaining white chocolate peanut butter into chunks. Put frozen chunks into a food processor and pulse 5 times so mixture takes on a coarse streusel-like appearance. Put sandy white chocolate peanut butter in a covered container in freezer until ready to assemble pie. Remaining white chocolate peanut butter may be kept in refrigerator or freezer depending on what you want to do with it. It will keep for at least 2 weeks in refrigerator and up to 6 months in freezer.

For the Chocolate Caramel Sauce: Put sugar and water into a medium sized saucepan and stir together until the mixture resembles wet sand. Add corn syrup and set pot over medium-high heat. Put a lid on pot and cook mixture for 5 minutes. Remove lid and sugar mixture should be bubbling. Continue to cook without stirring mixture until it reaches between 195°C-197°C, about 10 minutes. Sugar will be a medium amber colour.

Remove pan from heat and carefully add heavy cream. The mixture will boil violently. Put pan back on low heat and stir mixture together until caramel is dissolved. Remove pan from heat and let mixture cool until it reaches 55°C. Add chocolate and salt and stir mixture together until chocolate is fully incorporated.

Take about 1/4 of the sauce and use a pastry brush to spread it evenly over inside of cooled pie crust. Sprinkle half of frozen, streuselized white chocolate peanut butter over sauce, pressing it gently into crust if necessary. Reserve pie crust in freezer until you are ready to fill with ice cream.

Reserve remaining chocolate caramel sauce in a covered container at room temperature until you are ready to assemble pie. If you are not making the pie immediately, store caramel in refrigerator and let come to room temperature before using to finish the pie.

For the Caramelized Condensed Milk Ice Cream: Put 2 inches of water in bottom of a pressure cooker and add a small rack (the rack is usually included with every pressure cooker). Put condensed milk on rack and seal lid. Cook at high pressure for 90 minutes. Alternatively, cook canned condensed milk in a pot of boiling water for 3 hours, topping up the water as necessary.

Allow pressure to release naturally. Prepare an ice bath. Once depressurized, open lid and, using tongs, transfer can of caramelized condensed milk to ice bath. Let chill for at least 1 hour, adding more ice as needed, until completely cool: Do not open can while hot because a hot can of caramelized condensed milk is still under pressure and can erupt.

Put caramelized condensed milk, half of heavy cream and salt into the bowl of a stand mixer with whisk attachment. Turn mixer on low and increase speed to medium. Condensed milk will break apart and become absorbed into cream. Continue to whisk, about 5 minutes, until cream begins to thicken and caramelized condensed milk is dissolved in cream. Pour in remaining cream and increase speed to medium-high. Whip mixture until cream is at soft peaks. Turn mixer off and fold in the remaining sandy white chocolate peanut butter. Once inclusion is folded in, pour whipped mixture into prepared pie crust and freeze, uncovered for at least 4 hours and preferably overnight, until firm and frozen through.

To Finish the Snickers Pie: Take ice cream pie out of freezer once it’s fully frozen and use an offset spatula to spread remaining chocolate caramel sauce over top of pie in a thick layer. When ice cream is fully covered, sprinkle peanuts over top. Freeze pie for another hour to set frosting. Remove pie from freezer and let temper for at least 15 minutes. Slice and serve.