Preheat oven 350°F, grease 8x8 pan

mix butter and sugar, beat in eggs and vanilla

in separate bowl whisk flour, graham crackers, baking powder, and salt, then add to butter mixture

split mixture in half, press halfinto bottom of pan, lay candy bars on top of crust side by side, spread marshmallow fluff over chocolate bars, cover with remaining dough

bake 30-35 min