Preheat the oven to 350 and spray an 8×8 pan. (I like bakers joy for these kind of bars. It already has some flour in it and helps the bars come right out of the pan.)

In a large mixing bowl, cream the butter and sugars together.

Beat in the egg and the vanilla.

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

Add the flour mixture in to the butter mixture and beat on low until just combined.

Divide your cookie dough in half and gently press half of it in to the bottom of your 8×8 pan.

Chop up your candy bars in to small pieces and sprinkle them over the layer of graham cracker dough.

Spoon the whole jar of marshmallow cream over the top of the candy bars. (A good trick for this is to spray two spoons with canola spray and use one to scoop and one to scrape it off to get the marshmallow cream on to the candy bars. It will slip off the spoons easily and no messy fingers. Use the spoons to spread it gently until even.)

Put the other half of the cookie dough on to a large piece of waxed paper and use a rolling pin to get it in to a square that fits the top of the pan. (Use your fingers to help shape it.) Once it’s the right size, flip the dough on the waxed paper over on top of the marshmallow cream and peel the waxed paper right off!

Bake for 35 minutes until lightly browned. Make sure you let these bars cool completely before cutting them or you will end up with a gooey mess! (A delicious gooey mess, but a mess nonetheless!)