Place cereal into a food processor and blend until fine. Measure 2 1/2 cups of the cereal into a large bowl and set the rest aside. Add melted butter and salt to the cereal and mix until incorporated. Pour crust into a pie pan and mold to the form, bringing the cereal up the sides of the pan. Cover and freeze for 15 minutes, or until firm.
In a large bowl, mix together cream cheese, vanilla extract, powdered sugar, sour cream, heavy whipping cream, and the remaining cereal until combined and smooth. Pour the filling into the pie crust and smooth the top. Cover and return to the refrigerator for another hour until set.
Remove from the refrigerator and cover the top with even more cereal for garnish. Serve immediately.