With a name like Gooey Oreo Cookie Bars, it's no wonder these were a HUGE, huge hit with the taste testers. That included both grown ups and kids! Gooey Oreo Cookie Bars Ingredients 1/3 cup Hershey’s Dark unsweetened cocoa powder 1/2 teaspoon baking soda 1/4 teaspoon salt 1 1/4 cups flour 1/2 cup butter, soft