Step 1

Preheat oven to 350 degrees. Line a 8-inch square baking pan with foil and grease lightly.

Step 2

In a large bowl, cream together butter and sugar until light. Beat in egg and vanilla.

Step 3

In a small bowl, whisk together flour, graham cracker crumbs, baking powder and salt.

Step 4

Add to butter mixture and mix at a low speed until combined. Divide dough in half and press half of dough into an even layer on the bottom of the prepared pan.

Step 5

Place chocolate bars over dough. You may not need all of the chocolate, you only want a single layer, so break as needed to fit the pan.

Step 6

Spread chocolate with marshmallow creme.

Step 7

Place remaining dough in a single layer on top of the marshmallow layer (most easily achieved by flattening the dough into small pieces and laying them together).

Step 8

Bake for 30-35 minutes, until lightly browned.

Step 9

Cool completely before cutting into bars. Makes 24 bars.