Preheat the oven to 350 and get out a 9 x 13 baking dish. Pour the melted butter in to coat the bottom of the pan. Even distribute the graham cracker crumbs on top of the butter in an even layer, followed by the toffee bits, chocolate chips, coconut and the walnuts last. Pat the layers down to make sure they are compact and even. Pour the sweetened condensed milk all over the layers and let it seep in.
That's all there is to assembling the stir me nots! Bake them for 30 minutes, until golden and set. Take them out and let them cool for at least 10 minutes. Then cut them into squares and serve!