Start by preheating your oven to 350°F and lining a baking sheet with parchment paper.
Melt your butter until smooth, then whisk in both sugars, the egg, and vanilla extract until the mixture is silky and well combined.
1 stick Butter, 1/2 cup Brown Sugar, 1/4 cup White Granulated Sugar, 1 large Egg, 1 tsp Vanilla Extract
Next, gently fold in the dry ingredients—flour, baking soda, baking powder, and salt—just until no streaks remain.
1/2 tsp Baking Soda, 1/4 tsp. Baking Powder, 1/2 tsp Salt, 1 & 1/4 cup Flour
Stir in the mix-ins, adding pieces of graham crackers, chunks of chocolate (or chocolate chips if that’s what you have on hand), and plenty of mini marshmallows
1/2 cup Pieces of Graham Cracker, 1/2 cup Chocolate Chunks, 1/2 cup Mini Marshmallows
Using a large cookie scoop, portion out the dough onto your prepared sheet, spacing each cookie about two to three inches apart since they’ll spread while baking.
Bake for 10–12 minutes, or until the edges are golden and the centers look slightly underbaked.