Crunchy ginger crunch

“My Coeliac sister said she tried your crunchy ginger crunch and that it was life changing.”  So there you have it: cake that may change your life (or maybe just your afternoon). Better try it and see. Crunchy ginger crunch   For the base: 160g butter  150g brown sugar  160g fine polenta  160g gluten-free flour  1 teaspoon…