Preheat oven to 350. Spray a 9x13 inch pan with cooking spray and set aside.
Combine first five ingredients in a mixing bowl and beat with an electric mixer over medium speed until smooth. Stir in flour by hand, a bit at a time.
Press mixture into prepared pan and spread marshmallow creme over the top. Sprinkle evenly with chocolate chips and bake in preheated oven for 20-22 minutes until lightly browned. Remove from oven and allow to cool slightly. Sprinkle with graham cracker crumbs and allow to cool completely before cutting.
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Notes
How to Make Self-Rising Flour: Self rising flour is a bit different from all purpose flour. You can purchase it premixed at the store, or you can make it yourself at home if you don't have any of the store-bought version. For this recipe, simply whisk together 1 1/2 cups all purpose flour, 2 1/4 teaspoons baking powder, and 1/4 teaspoon + 1/8 teaspoon salt and use as directed.
How to Slice: The marshmallow creme can sometimes be a challenge to cut through because of its sticky composition. To remedy this, grab a sharp knife and run it under very hot water. Wipe off the excess liquid and slice. Clean off the knife and repeat for each additional cut. I like to use this method for cakes, too, for a nice clean cut!
Storing: Once the bars are sliced, place them in an airtight container and store on the counter for up to five days.
Freezing: Prepare and slice as directed. Cover the bars tightly in a container with both plastic wrap and aluminum foil. Freeze for up to 3 months. Thaw the bars overnight in the refrigerator before serving.
Gluten Free Option: In order to make these bars gluten free, first you will need to swap out the flour for your favorite gluten-free flour. I would recommend one of the blends from either Bob’s Red Mill or King Arthur Flour. Secondly, you will want to use a gluten free graham cracker, like this one from Pamela's available on Amazon. You could also try making your own homemade gluten free graham crackers.