Rhubarb Icebox Dessert

1 3/4 cups graham cracker crumbs, divided
3 tablespoons butter, melted
1 cup sugar
2 tablespoons cornstarch
4 cups diced fresh or frozen rhubarb
1 (3 ounce) package raspberry or strawberry gelatin mix
1 (8 ounce) carton frozen whipped topping, thawed
1 1/2 cups miniature marshmallows
2 cups cold milk
1 (3.4 ounce) package instant vanilla pudding mix

In a bowl, combine 1-1/2 cups cracker crumbs and butter. Press mixture into a greased 13-in. x 9-in. x 2-in. baking dish. Bake at 350°. for 10 minutes or until lightly browned. Cool on a wire rack.

In a large saucepan, combine the sugar, cornstarch and rhubarb. Bing to a boil; cook and stir for 2-3 minutes or until thickened and rhubarb is tender. Remove from the heat; stir in gelatin until dissolved. Cover and refrigerate for 1 hour or until partially set.

Spoon rhubarb mixture over crust. Combine whipped topping and marshmallows; spread over rhubarb mixture. In a bowl, whisk milk and pudding mix for 2 minutes. Let stand for 2 minutes or until soft-set. Carefully spread over marshmallow topping. Sprinkle with remaining cracker crumbs. Refrigerate for at least 2 hours before serving.