Pbj Crumb Bars

In small bowl, combine jam and cornstarch; set aside. Spread peanut butter in bottom and up sides of one frozen crust. Top with jam mixture. Sprinkle sugar and cinnamon in second frozen crust. Break or crumble crust into very small pieces and sprinkle on top of jam layer. Pour any sugar and cinnamon remaining in pie pan over broken crust pieces. Bake in preheated 400 oven or preheated baking sheet 20 to 25 minutes. Cool. Cut into bars.