Add butter to a light-bottomed medium pan and turn flame on to medium heat. It will begin to sputter and foam. Continue to stir the butter and keep on a medium heat, ensuring the solids do not burn at the bottom. The aromas from the browned butter should be intense with nutty and buttery notes. Let the butter brown; keep an eye on the butter for 5-7 minutes and turn off the heat. Scrape the browned bits and the browned butter into a bowl and set in the fridge for approximately 1 hour.
For the Blondies
Place 4 graham crackers into a food processor and blend until the crackers become very fine.
Cream butter and sugars together with a hand mixer.
To the creamed butter and sugar, crack in the eggs and vanilla extract mix.
To the wet ingredients, pour in the flour and baking soda and mix until the batter comes together.
Grease a 9x9 square pan and line with parchment paper. Pour the batter into the pan, then spread the batter evenly across the pan.
Top the blondie batter with chopped graham crackers and chocolate.
Last, add a generous helping of mini marshmallows, then bake for 24-25 minutes.