Preheat the oven to 350 degrees F. Lightly coat a quarter-size baking sheet with cooking spray, then line with parchment, allowing for a 2-inch overhang on the long sides. Coat the parchment with cooking spray.
Whisk together the all-purpose flour, whole-wheat flour, baking powder and salt. Set aside.
In the bowl of a stand mixer fitted with the paddle attachment, beat together the butter, brown sugar and honey for about 2 minutes. Add the eggs and vanilla; mix until light and fluffy, scraping down the sides of the bowl. Gradually mix in the flour mixture until fully combined.
Fold into the batter 3 cups of the marshmallows, 1 cup of the chocolate chips, all of the caramel bits, and half of the graham cracker pieces.
Spread the batter into the prepared baking sheet; sprinkle the remaining 1 cup chocolate chips and graham cracker pieces over the top. Transfer to the oven and bake for 25 minutes. Remove from the oven, top with remaining 1 cup marshmallows, and then bake for another 5 minutes.
Cool on a rack, then refrigerate to chill for easier cutting.
Cut into bars, being careful to remove parchment before serving.
Recipe courtesy of Trisha Yearwood