Line an 8x8 baking pan with parchment and set aside. Preheat your oven to 350°F.
If you haven't already, crush your graham crackers. They can be anywhere from finely crushed to mostly finely crushed with small pieces, just depending on your preference.
185 g Graham Crackers
In a small bowl, add your graham cracker crumbs, brown sugar, salt, and melted butter and stir together. It should create a sandy mixture.
15 g Dark brown sugar | 56 g Unsalted butter | ½ tsp Sea salt
Dump into your prepared pan and press down into an even layer. I like using a butter wrapper to help flatten the crumbs.
Bake your crust for 10-12 minutes, then remove from the oven.
In a light colored or stainless sauce pan, add your butter and place over medium heat. As the butter melts, it will first begin to bubble loudly, after this subsides it will begin to foam. Keep stirring as it foams to ensure the milk fats toast evenly and don't get stuck to the pan. When the butter becomes an amber color with a nutty fragrance, immediately transfer to a large bowl, making sure to scrape the toasted milk solids into the bowl as well.
140 g Unsalted butter
Add your sugars and vegetable oil to your browned butter and mix.
125 g Dark brown sugar | 100 g Granulated sugar | 1 tbsp Vegetable oil
Add your two whole eggs to the sugar and butter mix and mix well until the eggs are thoroughly combined.
2 large Eggs
Add your salt and vanilla and stir together.
½ tbsp Vanilla | 1 tsp Sea salt
Add your cocoa powder and mix in.
30 g Dutch processed cocoa powder
Add in your flour and stir until just combined, no dry bits remaining.
90 g AP flour
Add in the chocolate chips and stir to evenly distribute them throughout the batter.
125 g Chocolate chips
Pour your brownie batter into your pan over the crust and and smooth into an even layer.
Place your pan on the center rack of your oven and bake for about 22-25 minutes. When brownies are done the top will be set and shiny but if touched it will still be quite soft.
Turn off the oven and set to broil high.
Lightly arrange your large marshmallows on top of the brownies, covering the top.
35 Large Marshmallows
Place the brownies back in the oven under the broiler for about 2 minutes or until the tops of the marshmallows are toasted. Keep an eye on them as they will burn quickly.
Allow your brownies to cool in the pan for ideally at least two hours before cutting into them. They should be all the way cooled to room temperature to allow them to finish cooking and set. Store in an airtight container for 3-5 days, enjoy!
