Whisk sugar, cornstarch, and salt in a medium saucepan. Add milk and whisk a few times. Place the pan over medium-low heat, switch to a wooden spoon for stirring, and cook, stirring constantly, until thickened, about 5-8 minutes. Remove from heat once it is thick and coats the back of a wooden spoon.

Add the vanilla and peanut butter and stir until smooth.

Pour the pudding into a bowl and cover with plastic wrap (touch the plastic to the pudding, so a skin doesn’t form). Let cool to room temperature then cover with plastic wrap and refrigerate until set, at least 4 hours.

Prepare crust in a 9-inch pie plate. Chill until ready to fill.

Place 2 tablespoons (30ml) heavy whipping cream and chocolate chips in a small microwave safe bowl. Heat for 30 seconds, then whisk until smooth. Don’t overheat or you risk seizing the chocolate. Immediately spread the chocolate in the bottom of the crust, while it’s still hot. Chill while preparing filling.

Make whipped cream: Once pudding is set and you’re ready to assemble the pie, beat heavy cream with powdered sugar and vanilla until stiff peaks form. Fold half of the whipped cream into the pudding carefully. Place peanut butter mixture in prepared pie crust.

Top pie with remaining whipped cream and chopped peanuts and pretzels. Chill at least 1 hour before serving.

Store loosely covered in the refrigerator for up to 2 days.