Put crackers, sugar, and salt in a food processor and process until fine. Add butter and continue processing until combined.
Press evenly into bottom and up sides of a 9-inch pie plate. Bake crust until set, 9–11 minutes. Cool completely on a rack.
Combine cream and corn syrup in a saucepan and bring to a simmer. Place chocolate in a bowl and pour hot cream mixture over top. Let sit five minutes then whisk ganache until smooth. Set aside ¼ cup for topping. Pour remaining ganache over bottom of cooled crust; chill until set.
Peanut Butter Filling:
Whip the cream, 1/2 cup powdered sugar and vanilla in a stand mixer fitted with a whisk attachment on medium speed until thick peaks form.
Transfer whipped cream to a bowl. Set aside 2 cups in the fridge for topping.
In same mixer bowl (no need to wash), fitted with a paddle attachment, beat cream cheese until smooth. Add remaining 3/4 cup powdered sugar and peanut butter, beating until smooth and well combined. Fold in one-third of whipped cream until smooth, then fold in remaining two-thirds whipped cream. Spread filling evenly over ganache. Press a piece of plastic wrap over surface to prevent a skin from forming. Chill pie until firm, 4 hours, or overnight (the longer the better).
Spread the reserved 2 cups whipped cream over pie, drizzle with reserved ¼ cup ganache (reheat if needed) and peanut butter cups.