Have you ever had
magic cookie bars,
hello dolly bars or
seven layer bars? They're all the same thing generally consisting of a graham cracker crust, chocolate chips (and sometimes other baking chips as well), shredded coconut and chopped nuts all drizzled with sweetened condensed milk and baked until they stick together in a bar cookie.
Last year I wanted to do a cookie review activity where the kids earned ingredients for cookies for every program song they passed off. Originally I was thinking they would earn ingredients like flour, sugar, butter,... then I though that it would be even more fun if they could choose ingredients to make their own custom cookie. Enter the magic cookies! Okay, I grew up calling these cookies hello dolly bars, but I figured magic cookies would be more fun for primary.