Heat the oven to 350 degrees. Line a 13x9-inch baking pan with foil and coat with nonstick cooking spray. Combine the graham cracker crumbs, 1/4 cup of the sour cream and butter in a medium bowl. Press the crumbs into the bottom of the pan to form a crust. Combine the remaining 1/4 cup sour cream and sweetened condensed milk in a bowl and then pour over the crust. Sprinkle with coconut, chocolate chips, peanut butter chips, white baking chips and pecans. Press down firmly with a fork. Bake for 25 to 30 minutes or until lightly browned. Cool completely in the pan on a wire rack. Cut bars and serve.